Optical reader applicable to plurality of uses

ABSTRACT

An optical reader capable of reading a bar code in a mounted state when an article carrying the bar code passes and of reading bar codes set in array on a menu sheet in a hand-held state has been disclosed. The optical reader comprises a light source, a scanner that is driven by a drive and scans light emanating from the light source, a plurality of reflection mirrors that reflect scanning light scanned by the scanner and create a scanning pattern composed of a plurality of scan trajectories, a read window through which scanning light reflected from the reflection mirrors is emitted, and a light receiver for receiving light reflected from a mark. The optical reader further comprises a mode changer for changing a plurality of operation modes among which one or ones of the plurality of scan trajectories to be validated for reading are different. The operation modes include a specific scanning ray mode in which reading the mark by tracing only a given scan trajectory constituting the scanning pattern is validated but reading the mark by tracing the other scan trajectories is invalidated. For reading any of bar codes set in array on a menu sheet, the given scan trajectory constituting the scanning pattern will be drawn on a bar code to be read. Since reading by tracing the other scan trajectories is invalid, only the bar code to be read is read.

This application is a division of prior application Ser. No. 09/227,529filed Jan. 8, 1999 now U.S. Pat. No. 6,811,086, which is a division ofprior application Ser. No. 08/677,187 filed Jul. 9, 1996 now U.S. Pat.No. 6,216,953.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an optical reader, or moreparticularly, to a compact bar-code reader applicable to portable use.

In recent years, information input using bar codes has prevailed. Forexample, when a shopper purchases a product at a store, a bar-codereader is used to read a bar code carried by the product. Thus, theproduct code provided in the form of the bar code can be input and thepurchase can be registered.

For controlling inventories in a warehouse, it has become a matter ofdaily practice to read bar codes carried by the inventory or bycontainers for the inventory and to carry out inventory control on thebasis of the read data.

Thus, the bar-code reader is employed in information input for a varietyof applications. Bar-code readers of optimal forms (shapes or the like)are used for the respective applications. The present invention realizesa bar-code reader usable for various kinds of applications.

2. Description of the Related Art

Conventional bar-code readers are broadly divided by application intostationary readers and portable (hand-held) readers.

The stationary reader is literally a reader placed on, for example, acashier's counter or a conveyer for carrying articles. The stationaryreader has a read window. Scanning light such as laser light is emittedthrough the read window. The scanning light emitted through the readwindow is irradiated to an article bearing a bar code. The surface ofthe article is scanned by the scanning light. The scanning light scannedover the article is reflected. The reflected light is received throughthe read window, whereby the bar code is read. An article that is anobject of bar-code reading passes a position at a distance from thereader.

The orientations of bar codes passing in front of the reader are notalways a constant direction but are usually various directions(inclinations). A general stationary reader therefore produces scanninglight so as to generate a scanning pattern created by scanning raystraveling in a plurality of directions, in particular, a scanningpattern created by mutually-intersecting scanning rays.

A light reception sensor for receiving light reflected from a bar codeis incorporated in the stationary reader. Light reflected from abar-code surface is scattered light. A condenser for gathering as muchof the light reflected from a bar code as possible is therefore placedin front of the light reception sensor.

As mentioned above, the stationary reader is designed to read bar codesof articles passing a position away from the reader. The focal positionof scanning light emitted through the read window is therefore set to aposition away from the read window.

In the case of the stationary reader, a user is required to merely passarticles in front of the read window. Bar codes are then read out.Scanning for bar-code reading is very simple. Maneuverability isexcellent. In particular, even when it is required to read bar codescarried by a large number of articles for a limited period of time,since the articles need merely be passed in front of the reader,bar-code reading can be achieved efficiently.

The hand-held reader is a reader which is held in a hand and of whichthe read window is directed toward articles in order to read bar codescarried by the articles.

In the case of the stationary reader, since articles must be passed infront of the read window, when an article, for example, a heavy articleor large article is hard to pass the read window, the maneuver forreading is hard to do. In case an article contains liquid or an articlecannot be tilted, it is conceivable that the article may be passed infront of the read window but the bar-code surface thereof may not beable to be directed toward the read window.

In contrast, a hand-held reader is designed to approach an article forreading. Even if an article bearing a bar code is large or heavy, thebar code can be read readily. Even when an article cannot be tilted, abar code can be read by bringing the reader to the position of the barcode.

Herein, a gun-shaped reader has, similarly to the stationary reader, aform suitable for reading the bar code of an article located relativelydistant. The gun reader has a grip by which a user grasps and operatesthe reader.

In the case of the gun reader, a user holds the grip and directs a readwindow thereof toward a bar code to be read. A laser light source is litby manipulating a trigger switch formed on the grip. A scanning beam isthen emitted through the read window, whereby the bar code is read out.

Unlike the aforesaid readers, a touch-system reader is a reader that isbrought into contact with a bar code for reading or that is used to reada bar code located very near. A light source such as an LED and a lightreception sensor such as a CCD are incorporated in the touch reader. Forreading a bar code, a light source illuminates the bar-code surface.Light reflected from the bar code is then received by the lightreflection sensor.

There is a method to be adopted when bar codes cannot be affixeddirectly to products or the like, wherein: a plurality of bar codes arerecorded on a menu sheet in order to create a so-called bar-code menu;and when it is required to input product information, a necessary barcode is read out. Numerous different bar codes are recorded mutuallyadjacent on the bar-code menu. When an attempt is made to read thebar-code menu, only the bar code to be read must be read by the readerbut unwanted bar codes must not be read thereby.

However, in the case of the stationary reader or the like, scanning raysto be scanned in a plurality of directions (or sometimesmutually-intersecting scanning rays) are emitted. The scan range coveredby the stationary reader is very wide. When this kind of reader is usedto scan a bar-code menu, the possibility of scanning and readingunnecessary bar codes is very high. It is quite hard to scan only aspecific bar code. Moreover, for reading a bar-code menu using the gunreader, a method in which the reader is distant from or near to thereader menu is conceivable. In this case, when the gun reader is locatedat a distant position, it is hard to align a bar code with a positionscanned by the reader. When the gun reader is too close, the read windowinterferes with locating the position being scanned. When an attempt ismade to read a bar-code menu using either the stationary or gun reader,bar codes that need not to be read are read out. These readers aretherefore unsuitable for reading the bar-code menu.

By contrast, the touch reader is brought into contact with a bar code orlocated at a position very close to the bar code. A very limited rangealone is an object range of reading. The touch reader can easily readspecific bar codes alone selectively and is therefore very suitable forreading a bar-code menu.

As mentioned above, readers associated with bar-code read forms havebeen used in the past. The readers may be suitable for certainapplications but may not be suitable for other applications. The readersare applicable to only specific applications. For coping with variousread forms, readers associated with the read forms must be prepared.

For example, as mentioned above, it is difficult for the stationaryreader to read bar codes borne by articles that are difficult to pass infront of the read window; such as, heavy articles. When the bar codesborne by such articles must be read, the hand-held reader must be madeready to operate.

By contrast, in the case of the hand-held reader, it is required todirect the reader toward a bar code. Especially, in the case of thetouch reader, the reader must approach a bar code to such an extent thatit comes into contact with the bar code. The maneuverability for readingis poor. When numerous bar codes must be read in a short period of time,the use of the stationary reader is essential to improvement of readingefficiency.

Furthermore, since the stationary reader and gun reader scan a widerange, there is a possibility of reading excessive bar codes. Thestationary reader and gun reader are therefore unsuitable for reading abar-code menu. Especially, in the case of the gun reader, when thereader is too close to a menu sheet, a bar code is hidden behind theface of the reader. It becomes hard to locate a position of the menusheet being scanned or to check if a bar code that is an object ofreading is being scanned successfully.

When there is a possibility of reading a bar-code menu, the use of thetouch reader is needed. However, the touch reader cannot read a bar codelocated at a distance.

Consequently, optimal readers must be prepared for various read forms.However, preparing two or three kinds of readers for different readforms leads to an increase in cost involved in installing equipment.Besides, the case in which the use frequencies of readers dedicated todifferent applications are the same is rarer than the case in which theuse frequencies of some of the readers dedicated to specificapplications are higher. There is difficulty even cost-wise in preparingreaders, which operate in rarely-used forms, just in case.

For preparing readers that operate in a plurality of forms, an extraspace is needed to install the plurality of readers. However, only alimited space can be allocated to, for example, a cashier's counter.When a store itself is narrow, it cannot afford to install the pluralityof readers. In this case, the idea of installing the plurality ofreaders itself becomes a disadvantageous condition for the store.

SUMMARY OF THE INVENTION

An object of the present invention is to realize a reader applicable todifferent read forms.

For coping with different read forms using one reader, it is required tochange the reader among read modes associated with the read formswhenever ti becomes necessary. The present invention is characterized inthat it realizes a mechanism for manually or automatically changing readmodes optimally for the read forms in which a reader operates.

Furthermore, an object of the present invention is to assist in andfacilitate the user's work of reading by setting the emission directionof a scanning ray according to each read form or by indirectly notifyingthe user of the scan direction of a scanning ray.

Yet another object of the present invention is to design a stand neededto use a reader as a stationary reader so that the stand will beuser-friendly.

Still another object of the present invention is to improve an opticalsystem for a reader.

An optical reader according to the present invention scans a markcarried by an article using scanning light, detects light reflected fromsaid mark, and thus reads information represented by said mark. Theoptical reader comprises: a light source; a scanning means that isdriven by a driving means and scans light emanating from the lightsource; a plurality of reflection mirrors for reflecting scanning lightscanned by the scanning means and creating a scanning pattern composedof a plurality of scan trajectories; a read window through whichscanning light reflected from the reflection mirrors is emitted; and alight receiving means for receiving light reflected from the mark; and amode changing means for changing a plurality of operation modes amongwhich one or ones of the plurality of scan trajectories to be validatedfor reading are different, the plurality of operation modes including aspecific scanning ray mode in which reading the mark using only aspecific scan trajectory constituting the scanning pattern is validatedand reading the mark using the other scan trajectories is invalidated.

According to the present invention, in the specific scanning ray mode,only a specific scan trajectory is validated and the other scantrajectories are invalidated, therefore, other marks except a targetmark are not read. This is particularly effective when bar-codes on amenu sheet are read.

The read window is divided into a first area and a second area, scanningrays tracing the other scan trajectories are output through the firstarea, and a scanning ray tracing the given scan trajectory is outputthrough the second area. The first area is a first read window, and thesecond area is a second read window independent of the first readwindow. The emission direction of a scanning ray tracing the given scantrajectory is obliquely upwards relative to scanning rays tracing theother scan trajectories, and the second read window is located above thefirst read window, and the face of the second read window is locatedobliquely to the face of the first read window.

According to these constitutions, a user can easily recognize theposition from which the given scan trajectory is output.

The scanning means is a rotary polygon mirror that has a plurality ofreflection surfaces and that is driven to rotate by means of the drivingmeans, and at least one of the plurality of reflection surfaces isplaced at an angle, which is different from an angle at which the otherreflection surfaces are placed, with respect to an axis of rotation ofthe rotary polygon mirror. The reflection mirrors include a first groupof reflection mirrors for determining the other scan trajectories and asecond group of reflection mirrors for determining the given scantrajectory. The second group of reflection mirrors comprises a singlereflection mirror. The other scan trajectories are traced by a pluralityof intersecting scanning rays, and the given trajectory is traced by ascanning ray scanned in one direction. The focal position of scanningrays tracing the other scan trajectories is set to a position separatedby a first distance from the first area, and the focal position of ascanning ray tracing the given scan trajectory is set to a secondposition that is closer to the read window than the first position. Thesecond position lies on the face of the second area of the read window.A scan width on the read window permitted by a scanning ray tracing thegiven scan trajectory is larger than a scan width on the read windowpermitted by scanning rays tracing the other scan trajectories.

The optical reader comprises emission position indicating means forindicating positions between which a scanning ray tracing the given scantrajectory is emitted through the read window. The emission positionindicating means are marks inscribed on the sides of the read window.The emission position indicating means are indicating means forindicating the start point and end point of scanning light emittedthrough the read window and notifying a user of the fact that readingthe mark is completed. The emission position indicating means areprojections projecting from positions coincident with the start pointand end point of scanning light emitted through the read window. Theprojections are extending to the focal position of a scanning ray thatis emitted through the read window and that traces the given scantrajectory.

The second read window is located at a position away from the first readwindow. The optical reader further comprises a transparent coverattached to the face of the second read window, wherein the focalposition of a scanning ray that is emitted through the second readwindow and traces the given scan trajectory lies at the tip of thetransparent cover.

The optical reader further comprises a mode selection instructing meansfor instructing which of the plurality of operation modes should beselected, wherein the mode changing means selects an operation modeinstructed by the mode selection instructing means. The mode selectioninstructing means is a switch to be manipulated by a user. The switchhas a switch plate that is placed on the top of the switch and thatpressurizes the switch. The mode selection instructing means comprises aplurality of manipulable parts, and the contents of instruction made bythe instructing means are changed into the contents of instruction otherthan selection of any of the plurality of operation modes according towhether one of the plurality of manipulable parts is manipulated or theplurality of manipulable parts are manipulated simultaneously. The modeselection instructing means includes a detecting means located on atleast one of the lateral sides of the optical reader, and any of theplurality of operation modes is selected according to a mounted state ofthe optical reader which is detected on the basis of an output of thedetecting means.

The optical reader can be mounted in a specific holding member, the modeselection instructing means is a set detecting means for detectingwhether or not the optical reader is mounted in the specific holdingmember, and when the set detecting means detects that the optical readeris mounted in the specific holding member, an operation mode other thanthe specific scanning ray mode is selected. The set detecting means is aswitch to be pushed by a jut formed on the specific holding member whenthe optical reader is mounted in the specific holding member. The setdetecting means is a specific mark detecting means that when the opticalreader is mounted on the specific holding member, detects if scanninglight emitted through one of the areas of the optical reader hasdetected the mark. The optical reader further comprises a secondinstructing means for use in designating an operation mode, wherein anoperation mode is selected according to a combination of the state ofthe first instructing means and the state of the second instructingmeans.

The mode changing means gives control so that in the given operationmode, the light source will be lit only for a period during which ascanning ray tracing the given scan trajectory is being output. Thespecific scan trajectory validating means gives control so that in anymode other than the given operation mode, the light source is put outfor a period during which scanning rays tracing the other scantrajectories are being output. The specific scan trajectory validatingmeans gives control so that in the given operation mode, the operationof the light receiving means will be validated only for a period duringwhich a scanning ray tracing the given scan trajectory is being output.The specific scan trajectory validating means gives control so that inany mode other than the specific operation mode, the operation of thelight receiving means will be invalidated for a period during whichscanning rays tracing the other scan trajectories are being output.Invalidating the operation of said light receiving means is invalidationof the decoding of said read mark.

In the optical reader, the light source, scanning means, plurality ofreflection mirrors, read window, and light receiving means are stowed ina head. The optical reader further comprises a grip that is providedwith the head and enables a user to grasp the optical reader. The backside of the head is molded obliquely. The back side of the head ismolded to be angled in the emission direction of scanning light emittedthrough the second area. The back side of the head has a concave dentformed so that scanning light emitted through the second area can bediscerned.

The optical reader further comprises a notifying means for notifying auser of a selected mode. The notifying means is an indicating means, andthe indication form of the indicating means is varied depending on aselected mode. The indicating means selects continual indication orintermittent indication according to a selected mode. The notifyingmeans is a speaker for generating a notification sound, and thenotification sound is varied depending on a selected mode. The notifyingmeans is a means for reporting the result of reading of the mark, andthe notification form for the result of reading to be notified by thenotifying means is varied depending on a selected mode.

An optical reader according to a second aspect of the present inventionscans a mark borne by an article using scanning light, detects lightreflected from the mark, and thus reads information represented by saidmark. The optical reader comprises:

-   -   a light source; a scanning means that is driven by a driving        means and scans light emanating from the light source; a        plurality of reflection mirrors for reflecting scanning light        scanned by the scanning means and creating a scanning pattern        composed of a plurality of scan trajectories; a read window        through which scanning light reflected from the reflection        mirrors is emitted; a head including a light receiving means for        receiving light reflected from the mark; and a grip being        provided with the head and enabling a user to grasp the optical        reader.

A switch according to the present invention, comprises: a switch bodyincorporated in an apparatus; and a switch plate that is attached to thetop of said switch body and that depresses said switch body whenmanipulated, the switch plate is supported at two or more supportingpoints; and when the switch plate is manipulated, the switch plate ispivoted in a manipulated direction with the supporting points asfulcrums and the switch body is pressurized. The supporting points arethree supporting points arranged in the form of a triangle, and theswitch plate is held on the apparatus at the three supporting points.

A stand according to the present invention is used to hold an opticalreader. The optical reader has a read window through which scanninglight is emitted and a grip enabling a user to grasp said opticalreader, and which scans a mark borne by an article using scanning lightemitted through said read window, detects light reflected from saidmark, and thus reads information. The stand comprises: a holder sectionin which said grip is mounted so that said grip can be dismountedfreely; and

-   -   a base for supporting said holder section so that the holder        section can pivot, said holder section having a slit, through        which a cable coupled with the optical reader can pass, on the        same side thereof as the side of said optical reader having said        read window. A concave dent is formed from a position on the        base coincident with a lower end of the grip of the optical        reader mounted toward the forward side of the stand. The holder        section has a member to be actuated with an instruction sent        from the optical reader so that a state in which the optical        reader is mounted on the stand can be reported to the optical        reader. The member is shaped like a jut, and when the optical        reader is mounted on the stand, the member pushes the        instructing means. The member is a mark readable by the optical        reader, and the mark is located at a position enabling scanning        light emanating from the optical reader mounted on the stand to        scan the mark.

A stand according to another aspect of the present invention is used tomount an optical reader on it. The optical reader includes a read windowthrough which scanning light is emitted and a grip enabling a user tograsp the optical reader, and which scans a mark borne by an articleusing scanning light emitted through the read window, detects lightreflected from the mark, and thus reads information. The stand comprisesa stand member on which the optical reader is mounted in such a mannerthat the grip of the optical reader will face laterally. The standfurther comprises:

-   -   a holder section in which the grip is mounted so that the grip        can be dismounted freely; and a base for supporting said holder        section so that said holder section can pivot, the stand member        having a tongue, which is inserted into the holder section so        that the tongue can be removed freely, on a bottom thereof. When        the optical reader is mounted in the stand member, the optical        reader is held at an angle at which at least one scanning        pattern, which is composed of a group of scanning rays, of        scanning patterns created by scanning rays emitted through the        read window of the optical reader, becomes horizontal.

An optical unit for an optical reader according to the present inventioncomprises a plurality of reflection mirrors; a laser light source; alight reception sensor; a condenser mirror that has a plane mirror,which reflects laser light emanating from the laser light source, aroundthe center thereof and that gathers incident light to the lightreception sensor; a rotary scanning means that has a plurality ofreflection surfaces for reflecting laser light reflected from said planemirror, that is driven to rotate by means of a driving means, and thatthus scans the laser light; and a frame which is molded as a united bodyand in which the reflection mirrors, the laser light source, the lightreception sensor, the condenser mirror, and the rotary scanning meansare locked. The rotary scanning means is mounted on the frame viacushioning member. The condenser mirror has both edges thereof supportedby the frame; one edge of the condenser mirror is supported so that itcan move back and forth; the other edge of the condenser mirror issupported so that it can pivot with an axis of pivoting extending in alongitudinal direction of the condenser mirror as a center.

An optical unit according to another aspect of the present inventioncomprises:

-   -   an optical part having a first and second stems formed coaxially        on both edges thereof and a third stem formed vertically to the        second stem on one of the edges thereof; and a frame on which        the optical part is mounted, and which includes a first        slit-like bearing into which the first stem is fitted, a second        bearing into which the second stem is fitted, and a third        elongated bearing into which the third stem is fitted and which        forms an arc with the second bearing as a center.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be more clearly understood from thedescription as set below with reference to the accompanying drawings,wherein:

-   -   FIG. 1 is a diagram showing a conventional stationary reader;

FIGS. 2A and 2B are a sectional view and perspective oblique view of theconventional stationary reader;

FIG. 3 is a view showing a conventional gun reader;

FIG. 4 is a view showing a conventional touch reader;

FIGS. 5A and 5B are views showing a problem occurring when the gunreader is used to read a bar-code menu;

FIG. 6 is a front view of a reader of an embodiment of the presentinvention;

FIGS. 7A and 7B are a perspective oblique view and side sectional viewof the reader of the embodiment;

FIG. 8 is a diagram showing the emission direction of scanning lightreflected by a fourth reflection surfaces;

FIG. 9 is a diagram showing the emission direction of scanning lightreflected by a fourth reflection surface;

FIG. 10 is a diagram showing scanning patterns supplied by the reader ofthe embodiment;

FIG. 11 is a diagram showing scanning patterns within read windows;

FIG. 12 is a diagram showing scanning patterns at a distance from theread windows;

FIGS. 13A to 13C are views showing read forms permitted by the reader ofthe embodiment;

FIG. 14 is a view showing another embodiment of a reader;

FIG. 15 is a four-side view of the reader shown in FIG. 14;

FIG. 16 is a view showing a state in which the reader shown in FIG. 14is mounted on a stand;

FIG. 17 is a view showing a state in which the reader shown in FIG. 14is used as a hand-held reader;

FIG. 18 is a view showing a state in which the reader shown in FIG. 14is used to read a bar-code menu;

FIG. 19 is a diagram showing a structure for lighting a plurality ofindicators using a single light source;

FIGS. 20A and 20B are views showing a stand on which a reader ismounted;

FIG. 21 is a three-side view of a stand in accordance with anembodiment;

FIG. 22 is a four-side view of a stand on which a reader is mounted;

FIG. 23 is a view showing a pivotable range of a holder section of thestand;

FIG. 24 is a diagram showing a plate attached to the bottom of a base ofthe stand;

FIG. 25 is a diagram showing a state in which the plate is attached to awall;

FIG. 26 is a view showing a state in which the stand is hung on thewall;

FIG. 27 is a side sectional view of the stand hung on the wall;

FIG. 28 is an explanatory diagram concerning a stand tilt mechanism;

FIG. 29 is a side view of the tilt mechanism;

FIG. 30 is a front view of the tilt mechanism;

FIG. 31 is a view showing a laying stand and a stand body;

FIG. 32 is a view showing the laying stand on which the reader ismounted;

FIGS. 33A and 33B are views showing the laying stand on which the readeris mounted with the grip of the reader jutted out right and left;

FIG. 34 is a view showing an erecting stand;

FIG. 35 is a view showing a laying stand;

FIG. 36 is a view showing a polygon mirror having a mechanism forchecking a scan position;

FIG. 37 is a diagram showing the relationship between a sensor outputand mirror position detection signal;

FIG. 38 is a block diagram of a reader;

FIG. 39 is a flowchart describing a procedure of read mode change;

FIG. 40 is a flowchart describing light source lighting control to beperformed according to a floor mirror over which scanning light isscanned (read mode change);

FIG. 41 is a timing chart showing waveforms of output signals providedby the components of a reader during light source lighting control;

FIG. 42 is a view showing a mode selection switch formed on the backside of a reader;

FIG. 43 is a view showing a state in which the mode selection switch ismanipulated by an index finger;

FIG. 44 is a view showing a state in which the mode selection switch ismanipulated by a thumb;

FIGS. 45A and 45B are views showing a switch plate and a switch;

FIGS. 46A and 46B are diagrams showing a pressed position of the switchplate and fulcrums;

FIG. 47 is a view showing a reader having a switch on the front side ofa grip thereof;

FIG. 48 is a view showing a reader having side switches;

FIG. 49 is a timing chart concerning control of a light detectioncircuit according to the position of a floor mirror scanned by scanninglight;

FIG. 50 is a flowchart describing a procedure of light detection circuitcontrol;

FIG. 51 is a flowchart describing a procedure of decoding control;

FIG. 52 is a side sectional view of a reader in which a floor mirror E1′is movable;

FIG. 53 is a diagram concerning light source control performed by thereader shown in FIG. 52;

FIG. 54 is a flowchart describing a procedure of read mode changeperformed by the reader having the movable floor mirror;

FIG. 55 is a view showing a reader laid on a tabletop;

FIG. 56 is a view showing a reader having mode detection sensors on thelateral sides thereof;

FIG. 57 is a view showing a state in which the reader having the modedetection sensors is laid on a tabletop;

FIG. 58 is a flowchart describing a procedure of read mode change basedon the mode detection sensors;

FIG. 59 is a flowchart showing a procedure of read mode change in whichthe mode selection switch and mode detection sensors are used incombination;

FIG. 60 is a reader having detection switches on the lateral sidesthereof;

FIG. 61 is a flowchart describing a procedure of read mode change usingthe mode detection switches;

FIG. 62 is a view showing a reader of which stand has a detection jut onthe base thereof and which has a detector in the grip thereof;

FIG. 63 is a flowchart describing a procedure of read mode changeperformed by the reader shown in FIG. 62;

FIG. 64 is a flowchart describing another procedure of read mode changeperformed by the reader shown in FIG. 62;

FIGS. 65A and 65B are views showing a read mode change mark inscribed ona laying stand;

FIG. 66 is a flowchart describing a procedure of read mode change basedon the mark;

FIG. 67 is a view showing a reader having a grip sensor;

FIG. 68 is a flowchart describing a procedure of read mode change basedon the grip sensor;

FIG. 69 is a view showing a reader having a scan direction indicatormark;

FIG. 70 is a view showing a reader having LED indicators on the lateralsides thereof;

FIG. 71 is a view showing a reader having scan position indicatorprojections;

FIG. 72 is a view showing a reader having scan position indicator jutson a cover thereof;

FIG. 73 is a view showing a reader having a transparent cover;

FIG. 74 is a view showing a reader having a notch in a cover thereof;

FIG. 75 is a view showing a reader having a concave part on the backside thereof;

FIGS. 76A and 76B are views showing a scanning ray emission directionand the back side of a reader;

FIGS. 77A and 77B are diagrams showing the relationship betweenincidence and reflection of scanning light to and from a bar-codesurface;

FIG. 78 is a side sectional view of a reader;

FIG. 79 is a view showing an optical frame and optical parts;

FIG. 80 is a view showing the optical frame in which the parts arelocked;

FIG. 81 is a view showing the optical frame in which the parts arelocked;

FIG. 82 is a view showing the optical frame in which the parts arelocked;

FIG. 83 is a view showing the optical frame in which the parts arelocked;

FIG. 84 is a view showing a condenser mirror;

FIG. 85 is a view showing the condenser mirror to be attached to theoptical frame;

FIG. 86 is a view showing a reader that supplies a parallel-ray scanningpattern through a second read window;

FIG. 87 is a view showing a reader that supplies a raster-form scanningpattern through a second read window;

FIG. 88 is a side sectional view of a reader in which a floor mirror isdriven;

FIG. 89 is a flowchart describing a procedure of actuator drive;

FIG. 90 is a side sectional view of a reader in which scanning lightemitted through a second read window is condensed;

FIGS. 91A to 91C are diagrams for explaining the relationship between adiameter of light and bar-code reading;

FIG. 92 is a view showing another example of a reader in which scanninglight emitted through a second read window is condensed;

FIG. 93 is a block diagram of a reader;

FIG. 94 is a flowchart describing a procedure of changing indicators ofreading modes;

FIG. 95 is a flowchart describing a procedure of rumbling sound changeto be performed for notifying read modes using rumbling sounds;

FIG. 96 is a flowchart describing a procedure of rumbling sound changeto be performed for notifying read modes using long and short rumblingsounds;

FIG. 97 is a flowchart describing a procedure of rumbling sound changeto be performed for notifying read modes using large- and small-volumerumbling sounds;

FIG. 98 is a flowchart describing a procedure of rumbling sound changeto be performed for notifying read modes using the different numbers ofrumbling sounds;

FIG. 99 is a flowchart describing a procedure of rumbling sound changeto be performed for notifying read modes using high- and low-pitchrumbling sounds;

FIG. 100 is a flowchart describing indicator state change control to beperformed when read modes are notified according to the indication modeof indicators;

FIG. 101 is a view showing a reader having one read window (divided intoa plurality of areas);

FIG. 102 is a perspective oblique view showing a reader in which readingis validated in single-scanning mode during a period during which partof scanning rays constituting a multi-scanning pattern is emitted; and

FIG. 103 is a view showing the appearance of the reader shown in FIG.94.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Before proceeding to a detailed description of the preferred embodimentsof the present invention, prior art bar-code readers will be describedwith reference to the accompanying drawings thereto for a clearerunderstanding of the differences between the prior art and the presentinvention.

FIG. 1 is a view showing the appearance of an example of a stationarybar-code reader.

A stationary reader is placed on, for example, a cashier's counter or aconveyer for transporting articles. The stationary reader has a readwindow 13. Scanning light 10 such as laser light is emitted through theread window. The scanning light emitted through the read window isirradiated to an article bearing a bar code. The surface of the articleis scanned by the scanning light. The scanning light scanned over thearticle is reflected. The reflected light is received through the readwindow, whereby the bar code is read. Articles that are objects ofbar-code reading pass a position at a distance from the reader.

FIGS. 2A and 2B are views showing the internal components of thestationary reader shown in FIG. 1. FIG. 2A is a side sectional view ofthe reader, and FIG. 2B is a perspective oblique view of the internalcomponents of the reader.

A laser light source 21 for emitting laser light is incorporated by thereader. Laser light emanating from the laser light source is reflectedand scanned by a polygon mirror 22 that is driven to rotate by means ofa motor and that has a plurality of reflection surfaces, and then entersa patterning mirror 23.

The orientations of bar codes passing in front of the reader are notalways a constant direction but usually various directions(inclinations). A general stationary reader therefore produces scanninglight so as to generate a scanning pattern created by scanning raystraveling in a plurality of directions, or in particular, a scanningpattern created by mutually-intersecting scanning rays. In the readershown in FIG. 1, the scanning pattern is composed of three scanningrays.

For producing a plurality of scanning rays, the patterning mirror 23 isincorporated in the stationary reader. As shown in FIG. 2B, thepatterning mirror includes the same number of mirrors as the number ofscanning rays to be generated. In FIG. 2B, the patterning mirrorincludes three mirrors. A bar-code surface is therefore, as shown inFIG. 2B, scanned using the scanning pattern created by threeintersecting scanning rays. Due to this way of scanning, even if a barcode 41 is not level, the bar code can be scanned.

A light reception sensor 25 for receiving light reflected from a barcode is incorporated in the stationary reader. Light reflected from abar-code surface is scattered light. A condenser lens 24 for gatheringas much of the light reflected from a bar code as possible is thereforeplaced in front of the light reception sensor.

As described previously, the stationary reader is designed to read barcodes of articles passing a position away from the reader. The focalposition of scanning light emitted through the read window is set to aposition away from the read window.

In the case of the stationary reader, a user should merely have to passarticles in front of the read window. Bar-code reading is then carriedout. The maneuver for reader bar codes is very simple. Themaneuverability of the reader is therefore excellent. In particular,when it is required to read bar codes carried by a large number ofarticles for a short period of time, the articles should merely bepassed in front of the reader. Bar-code reading can be achievedefficiently.

FIGS. 3 and 4 are views showing an example of a hand-held reader. FIG. 3shows a so-called gun-shaped reader. FIG. 4 shows a so-calledtouch-system reader.

The hand-held reader is a reader which is held by a hand and of which aread window is directed toward an article in order to read a bar codecarried by the article.

In the case of the stationary reader, articles must be passed in frontof the read window. For an article, for example, a heavy article orlarge article that is difficult to make pass the read window, themaneuver for reading is difficult. When an article cannot be tiltedbecause it contains liquid, it is conceivable that even if the articlecan be passed in front of the read window, the bar-code surface thereofcannot be directed toward the read window.

In contrast, in the case of the hand-held reader, the reader canapproach an article for reading. Even if an article bearing a bar codeis large or heavy, the bar code can be read readily. As for an articlethat cannot be tilted, if the reader is drawn close to the position of abar code, the bar code can be read.

Similarly to the stationary reader, the gun reader has a form suitablefor reading a bar code of an article located at a relatively distantposition. The gun reader is, as shown in FIG. 3, broadly divided into ahead 11 and a grip 12. A light source, scanning mirrors including apolygon mirror and galvano-mirror, and a light reception sensor forsensing light reflected from a bar code are incorporated in the head.The grip is held by a user when the user operates the reader. A powersupply or the like may be stowed in the grip.

In the case of the gun reader, a user holds the grip and directs a readwindow 13 toward a bar code to be read. When a trigger-like triggerswitch 15 a formed on the grip is manipulated, a laser light source islit. A scanning beam is emitted through the read window, whereby the barcode is read.

Unlike the aforesaid readers, as shown in FIG. 4, the touch reader isbrought into contact with a bar code 41 for reading or used to read abar code located very close.

A light source such as an LED and a light reflection sensor areincorporated in the touch reader. For reading a bar code, a light sourceilluminates the bar code. Light reflected from the bar code is receivedby the light reception sensor.

There is a method to be adopted when a bar code cannot be affixeddirectly to a product or the like, wherein: a bar-code menu is createdby recording a plurality of bar codes on a menu sheet 4; and wheninputting product information is needed, a necessary bar code is read.Numerous different bar codes are recorded adjacently on the bar-codemenu. When an attempt is made to read the bar-code menu, only a bar codeto be read by a reader must be read but unwanted bar codes must not beread thereby.

However, in the case of the stationary reader, scanning rays to bescanned in a plurality of directions (or sometimes mutually-intersectingscanning rays) are emitted. The scan range covered by the stationaryreader is very wide. When this kind of reader is used to scan a bar-codemenu, the possibility of scanning and reading unwanted bar codes is veryhigh. Besides, it is very hard to scan only a specific bar code. Whenthe gun reader is used to read the bar-code menu, the reader maypresumably be distant from the bar-code menu as shown in FIG. 5A or nearto the bar-code menu as shown in FIG. 5B. In this case, when the readeris distant, it becomes hard to align a bar code with a scan position ofthe gun reader. When the gun reader is too near, the read windowinterferes with checking of a position being scanned.

When an attempt is made to read a bar-code menu using either thestationary or gun reader, a bar code that need not be read is read.These readers are therefore unsuitable for reading of the bar-code menu.

By contrast, in the case of the touch reader, the reader is brought intocontact with a bar code or approached very closely to the bar code. Aquite limited range is therefore an object range of reading. The touchreader can selectively read specific bar codes alone and is thereforevery suitable for reading of a bar-code menu.

As mentioned above, readers associated with bar-code read forms havebeen employed in the past. The readers are suitable for certainapplications but may not be suitable for other applications. The readersare applicable to only specific applications. For coping with variousrad forms, readers associated with the read forms must be prepared.

FIG. 6 is a view showing the appearance of a bar-code reader of anembodiment of the present invention.

The reader of this embodiment has the ability to cope with the formsassociated with the stationary reader, gun-shaped reader, andtouch-system reader. The one reader are therefore applicable todifferent uses.

In FIG. 6, reference numeral 1 denotes a reader body. 2 denotes a standon which the reader body 1 is mounted. The reader body 1 has a head 11,in which a light source, scanning means, and light receiving means(which are not shown) are incorporated, and a grip 12 that can be heldby a user.

A first read window 13 a and a second read window 13 b are formed on thefront side of the head 11. The first read window 13 a has a large area.In the reader shown in FIG. 6, the first read window is shaped like asector. The shape of the window is not limited to the one shown in FIG.6. The shape may be a square or the like. The second read window 13 ghas a smaller area than the first read window 13 a and has a straightlaterally-elongated shape. The shape of the second read window is alsonot limited to the one shown in FIG. 6.

The first read window 13 a and second read window 13 b supply a firstscanning pattern and second scanning pattern that are mutuallydifferent. The details of the scanning patterns will be described later.The scanning patterns associated with different read forms are supplied.

A cable 3 is coupled with an end of the grip 12. The other end of thecable 3 is coupled with an external unit such as a POS terminal that isnot shown. The cable 3 is used to supply power to the reader body 1 andto transmit read data (bar-code data) produced in the reader body 1 tothe external unit.

A speaker 19 for generating a notification sound used to notify a userof a result of bar-code reading is located on the front side of thereader.

FIGS. 7A and 7B are views showing the internal components of the readershown in FIG. 6, especially, of the head. FIG. 7A is a perspectiveoblique view showing the components from the side of the read windows ofthe head, and FIG. 7B is a side sectional view showing the head. InFIGS. 7A and 7B, the same functional parts as those in FIGS. 2A and 2Bare assigned the same reference numerals. The description of thefunctional parts will be omitted. A semiconductor laser or the like isused as a light source 21. Reference numeral 26 denotes a reflectionmirror (condenser mirror) realized with a concave mirror. A planar smallmirror 26′ is placed around the center of the concave mirror. Thereflection mirror 26 and small mirror 26′ may be provided as separatemembers and joined with each other afterward. Alternatively, thereflection mirror 26 and small mirror 26′ may be formed unitedly using,for example, a resin or the like. Thereafter, a reflection membrane maybe deposited on the united body. Light emanating from the light source21 is emitted toward the small mirror 26′.

The reflection surface of the small mirror 26′ is formed at such anangle that it allows laser light reflected from the small mirror 26′ tobe irradiated to a polygon mirror 22. The polygon mirror 22 shown inFIGS. 7A and 7B has a reflection surface on each of the four sidesthereof. The number of reflection surfaces is not limited to four. Thepolygon mirror 22 is attached to the shaft of a motor that is not shown,and driven to rotate by means of the motor. The inclinations (0) of thefour sides of reflection surfaces of the polygon mirror with respect toa vertical line are different from one another. The inclination of thepolygon mirror itself can be set freely. The inclination of one of thesides of the polygon mirror may be different from those of the othersides. Alternatively, all the sides may share the same inclination.

Laser light reflected from the reflection surfaces of the polygon mirror22 is scanned in responsive to the rotation of the polygon mirror andthen enters floor mirrors 23-1 to 23-8.

The floor mirrors are a plurality of mirrors and produce a plurality ofscanning rays constituting a scanning pattern. The floor mirrors shownin FIG. 2 are eight mirrors. Among them, the floor mirrors 23-1 to 23-5are arranged adjacently in such a manner that they define an arc. Allthe reflection surfaces are directed inward. The floor mirrors 23-3 and23-7 are placed above the floor mirrors 23-1 and 23-5 respectively, andthe reflection surfaces thereof are directed in the same direction asthose of the floor mirrors 23-1 and 23-5. The floor mirrors 23-1 and23-7 are placed under the first read window 13 a and constitute a firstgroup of floor mirrors.

The floor mirror 23-8 is placed under the second read window 13 b. Thefloor mirror 23-8 has a thinner and longer shape than the other floormirrors. A scanning ray emanating from the floor mirror 23-8 thereforelasts longer than those emanating from the other floor mirrors 23-1 to23-7 at the levels of the read windows.

Herein, assuming that a scanning ray permits a large scan width,compared with a scanning ray permitting a small scan width, a width tobe scanned by the former scanning ray within the same scan time islarger. In other words, as long as a width to be scanned is unchanged,the scan speed of the former scanning ray is lower. Bars of smallerthicknesses can therefore by detected. This leads to a substantialincrease in resolution. Thus, it is advantageous to increase a scanwidth permitted by a scanning ray. For increasing all scan widths, allthe floor mirrors must be made wider. This results in a larger head. Inthis embodiment, therefore, the floor mirror 23-8 alone is realized witha long mirror in consideration of the position of installation thereof.The floor mirror 23-8 is regarded as a second group of floor mirrors.

The numbers of floor mirrors constituting the first and second groups offloor mirrors can be properly selected according to read forms that arepresumably handled by the reader. The first and second groups of floormirrors may each include a plurality of floor mirrors. Scanning lightemitted from each of the first and second group of floor mirrors throughan associated read window should merely cope with a presumed read form.

Scanning light reflected from the polygon mirror 22 is reflected upwardin FIG. 7B by the floor mirrors 23-1 and 23-8 and emitted through theread window associated with the floor mirrors. Scanning light reflectedfrom the floor mirrors 23-1 to 23-7 is emitted through the first readwindow 13 a and creates a first scanning pattern. The first scanningpattern is therefore basically composed of seven scanning rays. Scanninglight reflected from the floor mirror 23-8 is emitted through the secondread window 13 b. A second scanning pattern is basically created by onescanning ray permitting a large scan width.

As shown in FIG. 7B, the mounting position of the floor mirrors 23-1 to23-5 and those of the floor mirrors 23-6 to 23-8 are deviatedvertically. As described previously, the reflection surfaces of thepolygon mirror have different inclinations. When laser light isirradiated to a reflection surface of the polygon mirror drawn with asolid line in FIG. 7B, scanning light is reflected from the floormirrors 23-1 to 23-5 along a path drawn with a solid line in FIG. 7B.Scanning light incident to the floor mirror 23-1 to 23-5 is reflectedupward, and emitted through the first read window 13 a.

By the way, a reflection surface of the polygon mirror drawn with adashed line in FIG. 7B faces up compared with the reflection surfacedrawn with a solid line. Scanning light (drawn with a dashed line inFIG. 7B) reflected by the reflection surface drawn with a dashed line isreflected upward more greatly than the scanning light reflected by thereflection surface drawn with a solid line, and then enters the floormirrors 23-8 and floor mirrors 23-6 and 23-7 which are mounted above thefloor mirrors 23-1 to 23-5. Of the scanning light, a scanning rayincident to the floor mirror 23-8 is reflected and emitted through thesecond read window 13 b. Scanning rays incident to the floor mirrors23-6 and 23-7, which are not shown, are reflected by the mirrors andemitted through the first read window 13 a.

As mentioned above, since the reflection surfaces of the polygon mirrorare inclined differently, a floor mirror to which scanning light isincident is selected according to a reflection surface by which thescanning light is reflected. A scanning pattern dependent on the floormirrors is supplied through an associated read window.

Light reflected from a bar code enters the light reception sensor 25along the same path as the emission path of scanning light. For example,reflected light of scanning light reflected by the floor mirror 23-1travels along the path of the first read window, floor mirror 23-1,polygon mirror 22, reflection mirror 26, and light reception sensor 25.Herein, light reflected from a bar code is scattered light. Forincreasing the quantity of light received by the light reception sensorG, the reflection mirror 26 that is a concave mirror is placed on thelight path. The reflection mirror gathers the light reflected from thebar code and routs it to the light reception sensor 25. The focalposition of the reflection mirror 26 is set on the light receptionsurface of the light reception sensor 25. This is intended to improvethe light reflection efficiency of the light reception sensor 25.

Next, emitting scanning light will be described.

FIGS. 8 and 9 are diagrams for explaining the emitted state of scanninglight. FIG. 8 shows a state in which scanning light is reflected by thefirst to third reflection surfaces of the polygon mirror, while FIG. 9shows a state in which scanning light is reflected by the fourthreflection surface of the polygon mirror.

As shown in FIG. 8, in case scanning light is reflected by the first,second, and third reflection surfaces of the polygon mirror(corresponding to the reflection surface drawn with a solid line in FIG.7B), the scanning light is reflected by the floor mirrors 23-1 to 23-5(the floor mirrors 23-4 and 23-5 are not shown), and emitted through thefirst read window 13 a. Herein, since the surfaces of the polygon mirrorhave different angles of reflection, a scanning ray reflected from thefirst reflection surface falls on a first position e1 of a floor mirror,a scanning ray reflected from the second reflection surface falls on asecond position e2 of the floor mirror, and a scanning ray reflectedfrom the third reflection surface falls on a third position e3 of thefloor mirror. Thus, the incident positions are different from oneanother.

The angles of incidence of the three scanning rays entering the floormirror are therefore different from one another. The emission directionof a scanning ray reflected from each floor mirror varies depending onthe incident position. For example, the scanning ray reflected from thefirst position e1 is emitted in a direction a in FIG. 8. The scanningray reflected from the second position e2 is emitted in a direction b inFIG. 8. The scanning light reflected from the third position e3 isemitted in a direction c in FIG. 8.

Since the emission directions of scanning rays thus differ from oneanother, a scanning pattern supplied through the first read windowvaries slightly in terms of scan position, and is available in threedifferent kinds. In the case shown in FIG. 8, the three scanning rays a,b, and c trace trajectories that are mutually parallel. Thus, when onescanning rays, a range scanned by the scanning rays can be expanded.This leads to an increase in probability of scanning a bar code passingin front of a read window. Eventually, it becomes possible to improvethe success rate of bar-code reading.

FIG. 9 shows a state in which scanning light is reflected by the fourthreflection surface of the polygon mirror (corresponding to thereflection surface drawn with a dashed line in FIG. 7B). The fourthreflection surface faces slightly up compared with the first to thirdreflection surfaces. The scanning light reflected from the fourthreflection surface of the polygon mirror therefore falls on the floormirrors 23-6 to 23-8 (the floor mirror 23-7 is not shown) mounted at aposition higher than the floor mirrors 23-1 to 23-5.

Of the scanning light, scanning rays reflected from the floor mirrors23-6 and 23-7 are emitted as a scanning ray b through the first readwindow. By contrast, a scanning ray reflected from the floor mirror 23-8is emitted as a scanning ray a through the second read window. Owing tothis structure, the read window through which scanning light is emittedcan be changed from one to the other according to the length of a periodduring which laser light is scanned.

As mentioned above, the number of scanning rays generated during onerotation of the polygon mirror can be increased by differentiating theinclinations of the reflection surfaces of the polygon mirror. Besides,the read window through which scanning light is emitted can be changedfrom one to the other.

FIG. 10 is a diagram showing scanning patterns supplied through thefirst and second read windows. Straight lines shown in FIG. 10 indicatetrajectories of scanning rays. Reference numerals assigned to thescanning rays indicate the associated floor mirrors and reflectionsurfaces of the polygon mirror. For example, 23-1 denotes a trajectoryof a scanning ray reflected from the floor mirror 23-1, and implies thatthis scanning ray is reflected from the first reflection surface of thepolygon mirror.

Straight lines 23-1 to 23-7 indicate trajectories of scanning raysemitted through the first read window. Straight lines 23-8 indicates atrajectory of a scanning ray emitted through the second read window.

Scanning rays reflected from the first to third reflection surfaces ofthe polygon mirror fall on the floor mirrors 23-1 to 23-5. Each of thefloor mirrors therefore generates three scanning rays during onerotation of the polygon mirror. Three scanning rays reflected from thefloor mirrors trace trajectories that are mutually parallel with givengaps among them.

A scanning ray emanating from the floor mirror 23-1 is substantiallyhorizontal relative to the read window. Scanning rays emanating from thefloor mirrors 23-2 and 23-5 are angled substantially at 45°. Thescanning ray emanating from the floor mirror 23-2 angles right, whilethe scanning ray emanating from the floor mirror 23-5 angles left.

Likewise, a scanning ray emanating from the floor mirror 23-3 anglesright, while a scanning ray emanating from the floor mirror 23-4 anglesleft. These scanning rays are angled more sharply than those emanatingfrom the floor mirrors 23-2 and 23-5.

Scanning light reflected from the fourth reflection surface of thepolygon mirror enters the floor mirrors 23-6 to 23-8. While the polygonmirror is making one rotation, each of the floor mirrors 23-6 to 23-8generates one scanning ray.

A scanning ray emanating from the floor mirror 23-6 is scanned atsubstantially the same angle as (but is slightly mismatched with) theone emanating from the floor mirror 23-2. The scan position of thescanning ray is a position at which the scanning ray emanating from thefloor mirror 23-2 does not scan. Likewise, the inclination of a scanningray emanating from the floor mirror 23-7 is slightly different from thatof the one emanating from the floor mirror 23-5. The scan position ofthe scanning ray is a position at which the scanning ray emanating fromthe floor mirror 23-5 does not scan.

Each of the floor mirrors 23-6 and 23-7 generates one scanning rayduring one rotation of the polygon mirror. Owing to this small number ofscanning rays emanating from each of the floor mirrors 23-6 and 23-7,the number of scanning rays emitted through the first read window can beincreased. Eventually, the possibility that a bar code is scanned beimproved.

As mentioned above, scanning rays to be scanned are emitted in aboutfive directions through the first read window. Even if bar codes passingthe first read window are tilted in various directions, any of thescanning rays can scan the bar codes in units of a readable length.Consequently, the probability of reading a bar code can be improved. Ascanning pattern dependent on the floor mirrors 23-1 to 23-5 is createdby three scanning rays that are scanned mutually parallel. Even if a barcode passes a position that may not be able to be scanned by a singlescanning ray, since the number of scanning rays is large, a wide scanrange is ensured. Consequently, if a plurality of scanning rays areemployed, any of them can scan the bar code. Eventually, the probabilityof reading a bar code further improves.

A scanning ray emanating from the floor mirror 23-8 is scannedhorizontally and emitted straight through the second read window.Herein, the length of the floor mirror 23-8 is longer than those of theother floor mirrors 23-1 to 23-7. The scanning ray emanating from thefloor mirror 23-8 therefore lasts longer.

A scanning ray emitted through the second read window has the scandirection thereof fixed. The scanning ray is therefore suitable for abar code or an object of reading of which orientation is determined inadvance or for a bar code of which position can be aligned in adirection optimal for reading.

Thus, the reader of this embodiment produces a total of 18 scanning raysduring one rotation of the polygon mirror.

In the example of FIG. 10, each of the floor mirrors 23-6 to 23-8produces one scanning ray during one rotation of the polygon mirror. Thenumber of scanning rays emanating from each floor mirror can be variedby modifying the number of reflection surfaces of the polygon mirror fortransmitting scanning light to floor mirrors. The number of scanningrays emanating from each floor mirror is therefore not limited to thevalue shown in FIG. 10. The reader shown in FIG. 10 has the preconditionthat only one scanning ray is emitted through the second read window.

FIG. 11 is a diagram showing trajectories constituting scanning patternson read surfaces. As shown in FIG. 11, a total of 17 scanning rays areemitted through the first read window, while one scanning ray permittinga long scan width is emitted through the second read window.

FIG. 12 is a diagram showing trajectories of scanning rays at a distancefrom the read windows. In this case, examples of scanning rays at aposition distanced by 100 mm from the read windows are shown. Comparedwith the scanning patterns shown in FIG. 11, the scanning patternsspread widely as a whole. As shown in FIG. 11, the larger the distancefrom the read windows is, the more widely the scanning patterns spread.Consequently, even if the position of a bar code passing a position awayfrom the reader is a position off the center of a read window, theprobability that the bar code is scanned is high. Eventually, thesuccess rate (read probability) of reading a bar code improves.

FIGS. 13A to 13C are views showing the usages of the reader of thisembodiment. FIG. 13A shows an example of using the reader as astationary reader. FIG. 13B shows an example of using the reader as agun reader. FIG. 13C shows an example of using the reader as a touchreader.

For using the reader as a stationary reader, the reader body is mountedon the stand. In this case, the grip of the reader is inserted into aholder section of the reader is inserted into a holder section of thestand. Thus, the reader body is immobilized and the read windows face ina given direction.

For reading bar codes in this state, articles bearing bar codes arepassed with the bar codes opposed to the read window employed. Asalready described, a scanning pattern 10 permitting scanning in aplurality of directions is supplied through the first read window. Thescanning rays scan a wide range. As shown in FIG. 13A, a bar code isscanned by numerous scanning rays having different inclinations. Forreading bar codes using the stationary reader, the inclinations of thebar codes passing the read window are not constant as long as a user isnot especially conscious of them. However, since a bar code is scannedusing the above scanning pattern, even if a bar code passing the readwindow employed is tilted, the possibility that the bar code is scannedby any of the scanning rays is high.

For using the reader as a gun reader, as shown in FIG. 18B, a user holdsthe grip and directs the read window employed toward a bar-code surfacelocated at a far position. The bar-code surface is then scanned usingthe scanning pattern. When the reader is used as a gun reader, bar codesare often at a distance from the read window. Similarly to those scannedby the stationary reader, the bar codes do not have a constantinclination. In particular, bar codes supposed to be read by a gunreader include those located beyond one's reach and those carried byheavy articles. In some cases, the orientations of bar codes cannot bechanged. Even when the reader is used as a gun reader, the scanningpattern supplied through the first read window is used to read barcodes. The scanning pattern spreads more widely as it gets farther fromthe read window employed. If the read window employed is only aimedroughly at a bar code, the desired bar code can be scanned.

For using the reader as a touch reader, as shown in FIG. 13C, a userholds the grip of the reader body. The second read window is thenbrought to the position of a specific bar code on, for example, abar-code menu. A scanning ray emitted through the second read window isused to scan the bar code that is an object of reading. The scandirection of the scanning ray emitted through the second read window isfixed. Since the bar-code menu is placed near the user's hand, it iseasy to align the bar code.

When the scanning pattern supplied through the second read window ismade different from that supplied through the first read window so thatmutually-intersecting scanning rays to be scanned in many directionswill not be produced, the scan range of the scanning ray emitted throughthe second read window is a quite limited range. For example, when ascanning ray that is emitted through the second read window is only theone scanned in one direction as shown in FIG. 10, the scanning patternsupplied through the second read window merely enables horizontal andlinear scanning of a scan surface.

A bar code is in principle long sideways. When scanned in a directionalong the shorter edges of a bar code, the bar code cannot be read. Ascanning ray emitted through the second read window is thereforedesigned to be scanned in one direction. Consequently, a bar code thatis not an object of reading or any other unwanted area will not bescanned. Reading an unwanted bar code or an incidence posing a problemwhen a bar-code menu is read can be avoided.

When the reader is used as a touch reader, it is possible to align theinclination of a bar code with the read window employed. Scanning rayshaving different scan directions are therefore unnecessary. When thereader is used as a touch reader, therefore, one scanning ray emittedthrough the second read window and scanned in one direction is used toread bar codes.

A scanning ray has a minimum diameter at a focal position. The smallerthe diameter is, the thinner the readable bars of a bar code are. When abar code is located at (or in the vicinity of) the focal position of ascanning ray, even if the bar code consists of thin bars, readingsucceeds. It is therefore preferable that a position at which a scanningray is focused be in the vicinity of the position of a bar code to beread in each read form.

When the reader is used as a stationary or gun reader, bar codes pass aposition away from the read window employed. It is therefore preferablethat the focal position of scanning rays emitted through the first readwindow be a position away from the read window, for example, a positionseveral tens of centimeters away therefore. For a larger read range, itis required that a readable area is realized ahead and behind the readwindow. Consequently, a read depth permitted by scanning rays emittedthrough the first read window should preferably be large.

When the reader is used as a touch reader, a bar code is located veryclose to the read window employed. It is therefore preferable that thefocal position of a scanning ray emitted through the second read windowbe on or near the second read window. Moreover, since the spacingbetween a bar code and the read window is not so large, the read depthof a scanning ray emitted through the second read window may be small.

When the reader is used as a touch reader, if the read depth of scanninglight emitted through the second read window is large, a bar codelocated at a position away from the second read window is also scanned.In this case, the possibility of reading a bar code that need not beread is high. For reading a bar-code menu, especially, while the readeris being moved to a desired bar code, it passes over the other bar codesrecorded on the menu sheet. At this time, there is a possibility thatthe scanning light may scan the other bar codes and read them. The barcodes recorded on the menu sheet are valid data irrespective of whetheror not they are objects of reading. While the reader is being moved, ifunnecessary bar codes are read, unwanted information is input to cause aproblem.

For preventing the occurrence of a problem, it is preferable that theread depth of scanning light emitted through the second read window besmall.

FIG. 14 is a view showing a variant of the reader of this embodiment. Areader shown in FIG. 14 has, unlike the reader shown in FIG. 6, thefirst read window and second read window thereof angled differently.

Scanning light emitted through the first read window is emittedhorizontally or slightly downward in FIG. 14 with the read windowdirected substantially in a vertical direction. When the reader ismounted on the stand, it is preferable, in consideration of the heightof the read window and a position at which an article bearing a bar codepasses, that the scanning light emitted through the first read window beangled slightly downward.

In contrast, the emission direction of scanning light emitted throughthe second read window is obliquely up.

A conventional touch reader uses an LED as a light source to illuminatethe whole of a range having almost the same size as a read window. Touse the conventional touch reader, a user should merely aim at a properposition so as to put the read window employed in the vicinity of a barcode. The bar code is then illuminated entirely by light emanating fromthe LED, and can be read.

However, in the case of the reader of this embodiment, what is emittedthrough the second read window is a linear scanning ray (laser light)alone. A range illuminated by the scanning ray is linear. In this case,unless a bar code is placed exactly at a position at which the scanningray passes, the bar code will not be scanned by the scanning ray andcannot be read. For reading an intended bar code correctly, therefore,it is important to locate a position at which a scanning ray scans and aposition of a bar code and to align a read window with the bar code.

When a user's line of vision and an emission direction of scanning lightemitted through the second read window are coincident with each otherand a bar code lies on an extension of the emission direction ofscanning light, it is easy to align the read window with the bar code.When the reader is used as a touch reader (in particular, when abar-code menu is placed on a tabletop), a bar code that is an object ofreading is located obliquely ahead of a user. For reading a bar-codemenu, a user is thought to bring the reader into oblique contact withthe bar code for reading. The reader of this embodiment is realized fromthis viewpoint. The emission direction of scanning light emitted throughthe second read window is, as illustrated, obliquely up. A user cantherefore easily aim at the position of a bar code. The emissiondirection of scanning light emitted through the second read window and auser's line of vision can be coaxially coincided with each other.

In the case of FIG. 14, three scanning rays having differentinclinations are emitted through the first read window. One scanning raypermitting a large scan width is emitted through the second read window.Incidentally, the number of scanning rays is not limited to the oneshown in FIG. 14.

FIG. 15 is a four-side view of the reader shown in FIG. 14. A plan viewis seen in the left upper area in the drawing, a side view is seen inthe left lower area, a back view is seen in the right lower area, and atop view is seen in the right upper area. A cover 14 molded using amember having elasticity, for example, rubber is attached to theperimeter of the second read window. When the second read window is usedto read a bar code, the cover prevents the second read window fromcoming into direct contact with a surface bearing a bar code or the likeand being flawed. Moreover, the cover absorbs impact occurring when theread window is brought into contact with the bar-code surface. Inaddition, the cover exerts the operation of a spacer for separating abar code and the second read window optimally for reading of the barcode. When this kind of cover is attached, a bar code that is an objectof reading is located around the tip of the cover. Consequently, thefocal position of scanning light emitted through the second read window(a position at which the scanning light is focused) should preferably bethe position of the tip of the cover or a position slightly ahead of thetip.

Indicators 16 a and 16 b for notifying a user of whether or not a barcode has been read normally are located on the upper margin of thesecond read window and on the back side of the reader respectively. FIG.14 shows an example in which an indicator 16 b is located on the cover14 attached to the perimeter of the second read window. An indicator onthe back side is not shown.

The indicators 16 a and 16 b are lit when a bar code is read normally orreading a bar code fails, whereby a user is notified of a bar-codereading situation.

Another mechanism for notifying a bar-code reading situation is aspeaker for giving a reporting sound.

Moreover, a mode selection switch 15 b is located on the back side ofthe reader. The operation of the mode selection switch will be describedin detail later. In short, the mode selection switch is used to change aread mode in which a bar code is read using scanning light emittedthrough the first read window into a read mode in which a bar code isread using scanning light emitted through the second read window, orvice versa.

A cable is coupled with the rear end of the grip, though it is not shownin FIG. 15.

FIG. 16 is a view showing a state in which the reader shown in FIG. 14is mounted on the stand and used as a stationary reader. When the readeris used as a stationary reader, a scanning pattern (A multi-scanningpattern. Scanning using the multi-scanning pattern is referred to asmulti-scanning.) being supplied through the first read window andpermitting scanning in a plurality of directions is sued to scan barcodes. In this case, when the reader is placed to have such a positionalrelation that it is opposed to a user, scanning light is emitted towardthe user through the read window. When the reader is thus placed, themaneuver for reading can be achieved readily.

Moreover, since the range scanned using a scanning pattern suppliedthrough the first read window 13 a 10 c is wide, when a bar code 4passes through a scan area 10 c, the bar code can be read. When a userintends to have a bar code read, he/she need not be so greatly consciousof a position at which an article 100 is passed. The wider the scan areais, the greater is the freedom of setting a position as an articlepasses.

Incidentally, a dent 5 for guiding the cable 3 coupled with the end ofthe grip to the forward side of the stand is formed on the base of thestand.

FIG. 17 is a view showing an example of using the reader as a gunreader. When the reader is used as a gun reader, a user holds the gripand directs the first read window toward a bar code borne by an article.Even in this case, multi-scanning is performed for reading. This usageis suitable for a case in which it is hard to match the position of abar code with a specific direction.

FIG. 18 is a view showing a case in which the reader shown in FIG. 14 isused as a touch reader. In the case shown in FIG. 18, the reader isbrought to the position of a specific bar code on a bar-code menu 4. Thebar code that is an object of reading is thus approached to the secondread window. The reader shown in FIG. 14 has the second read windowslightly inclined relative to the first read window. The second readwindow faces slightly up. For reading a bar code, the bar-code menu isoften placed on a desk or the like for reading. The reader is held overthe bar-code menu. When the second read window is inclined as shown inFIG. 14, and when the second read window approaches a bar code, thesecond read window can be bought into contact with the bar code in anatural manner.

As already described, the reader is provided with indicators, such asLEDs, that, when reading a bar code has completed normally, notify auser of the fact. When the reader is used as a stationary reader, theuser is opposed to the read window. For the use of the reader as astationary reader, therefore, an indicator should be formed on a readwindow so that it can be discerned easily.

When the reader is used as a hand-held reader, a user cannot discern theread window but can merely see the back side of the reader. If anindicator were located only on a read window, the user using the readeras a hand-held reader would have difficulty in discerning the indicator.However, since another indicator is located on the back side of thereader, the user can discern the indicator even when using the reader asa hand-held reader.

In the reader shown in FIG. 14, an indicator is located on each of theread window and the back side of the reader, so that the lit state of anindicator can be checked from either the front or back side of thereader. As for the indicators, different indicators may be placed on thefront and back side of the reader respectively. A light source (LED orthe like) for indication may be shared by the indicators. Lightemanating from the LED may be guided to the front and back sides so thatthe plurality of indicators can be lit simultaneously. For reducing thenumber of parts, the same light source should preferably be shared.

FIG. 19 is a diagram showing the structure of the indicators sharing thesame LED light source. In the case shown in FIG. 19, an LED light source5 is placed on the back side of the reader. A clear member 53 made of aresin or the like is located ahead of the LED light source.

When light is passed through a transparent member, if the angle ofincidence of the light incident to a wall of the member is equal to orsmaller than a critical angle, the incident light is reflected fully. Ifthe angle of incidence of the light is larger than the critical angle,the incident light is emitted outside from the wall of the member.

The indicators shown in FIG. 19 are realized by making the most of theforegoing nature of light.

One end of the clear member is, as mentioned above, provided with theLED light source 51, and the other end thereof serves as the indicator16 b located on the second read window 13 b. An opalescent member 52 isplaced at an end of the clear member 53 in the vicinity of the LED lightsource 51, whereby the indicator 16 a on the back side of the reader ismaterialized.

Light emanating from the LED light source enters the clear member 53.Light entering the wall of the clear member at an angle equal to orsmaller than the critical angle is guided to the indicator 16 b locatedon the second read window 13 b. Thus, the indicator on the second readwindow is illuminated.

By contrast, light emanating from the LED light source 51 and enteringthe wall of the clear member at an angle equal to or larger than thecritical angle passes through the clear member and is emitted outside.The opalescent member is located at a position at which light emanatingfrom the LED light source is emitted outside. Light emanating from theLED light source is therefore emitted directly through the opalescentmember, whereby the indicator on the back side of the reader isilluminated. The opalescent member acts as a plane of diffusion andscatters light emanating from the LED light source. A user can thereforediscern the contents of indication made by the indicators in a widerange.

Owing to the foregoing structure, the common LED light source 51 is usedto allow the indicators 16 b and 16 a located on the front and backsides of the reader to make indication for notifying a bar-code readingsituation.

FIGS. 20A and 20B are views showing the stand on which the reader ismounted. The reader is in the same as the reader shown in FIG. 16. FIG.20A is an oblique view and FIG. 20B is a side view.

As already described, the grip 12 of the reader is inserted into theholder section 62 of the stand. Thus, the reader 1 is fixed to the stand2. Since the cable 3 is extending from the bottom of the reader, a notch63 is formed on the front side of the holder section for fear the cable3 may interfere with mounting or dismounting of the reader on or fromthe stand 2.

For using the reader as a stationary reader, the reader is positioned sothat the read window thereof will be opposed to a user with a counter orthe like between them and scanning light will be emitted toward theuser. This layout facilitates the work of bar-code reading. By contrast,for using the reader as a hand-held reader, the reader must bedismounted from the stand and drawn close to the user.

In consideration of the foregoing usages, it is required to form anotch, through which the cable of the reader can be led out, on theholder section of the stand for fear the cable may interfere withmounting or dismounting of the reader on or from the stand. From theviewpoints of the position of the reader used as a stationary reader andof the work of mounting or dismounting the reader on or from the stand,the notch should preferably be formed on the front side of the holdersection facing a user.

Moreover, a dent 4 is formed on the base of the stand so that it willextend from under the holder section of the stand toward the user side.When the reader is mounted on the stand, the cable lies in the dent. Thecable can thus be led into the user side. The cable coupled with the endof the grip cannot be bent very sharply. Forming the dent on the base ofthe stand is therefore effective in the sense of protecting the cable.

The holder section is pivotable in arrow directions in FIGS. 20A and 20Brelative to the base of the stand. The read window employed of thereader and the emission direction of scanning light emitted through theread window can be set at a desired angle. As shown in FIG. 20B, theemission direction of scanning light emitted through the read windowemployed can be adjusted freely within the pivotable range of the holdersection.

FIG. 21 is a three-side view of the stand on which the reader of thisembodiment is mounted. In FIG. 21, a top view is seen in the left upperarea, a front view is seen in the left lower area, and a side sectionalview is seen in the right upper area. The holder section of the stand issupported at two points by the base. The points serve as fulcrums. Thedent formed on the base has a shape spreading toward the edge of thebase. The tip of the holder section is made wider so that the end of thegrip of the reader can be introduced readily.

The stand shown in FIG. 21 is made of, for example, a resin.

A spring is located at one of the fulcrums of the holder section. Alocking member 624 is attached to the other end of the spring. A platesuch as a metallic plate is screwed to the bottom of the base. Thesecomponents will be described in detail later.

FIG. 22 is a four-side view showing a state in which the reader ismounted on the stand. In FIG. 22, a back view is seen in the left upperarea, a side view is seen in the left lower area, a front view is seenin the right lower area, and a top view is seen in the right upper area.As shown in FIG. 22, when the reader 1 is mounted on the stand 2, Theread windows (especially the first read window) can be placed at properheights and fixed in desired directions. The reader is merely insertedinto the holder section of the stand and locked in the holder sectionowing to its own weight. The work of mounting or dismounting the readeron or from the stand (especially dismounting) can be achieved readily.

FIG. 23 is a view showing adjustment of an angle at which the holdersection of the stand is set. In the case shown in FIG. 23, the righthand of the drawing is the user side. FIG. 23 shows three states; astate in which the reader is mounted upright, a state (a) in which thereader is tilted toward the user side to the greatest extent and thefirst read window faces down, and a state (b) in which the reader istilted toward the side opposite to the user side to the greatest extentand the first read window faces fully up.

As shown in FIG. 23, the angle of the reader can be adjusted freelywithin a range from a position a to b. The reader can be set at anoptimal angle according to the installation site of the reader or theusage of the reader.

The stand can not only be placed on a counter but also, for example, behung on a wall. When the stand is hung on a wall, the reader isimmobilized at the position b in FIG. 23.

In case the wall has a metallic surface, a magnet or the like may beattached to the bottom of the stand so that the stand can be attractedto the wall. When the wall does not have the metallic surface, the standis hung as described below.

As shown in FIG. 21, a screw hole 601 is formed around the center of thestand base. The screw hole is used to screw the stand 2 to a wall. Thestand can thus be hung on the wall. However, when the stand is supportedat only one point, there is a possibility that the stand rotates withthe screwed point as a center. The stand cannot therefore be fixed tothe wall on a stable basis.

A method of preventing the rotation of the stand is a method in which aplurality of screw holes are formed in the stand. If this method wereadopted, since the stand is fixed at the plurality of points, the standwill not rotate. However, since numerous holes are bored in the stand,the appearance is not good.

A plate 611 such as a metallic plate is therefore, as shown in FIG. 19,attached to the bottom of the stand base of this embodiment. The platemay have, for example, a round shape. The shape of the plate is notlimited to the one shown in FIG. 24. Supposing the plate is a metallicplate, since the plate has weight, it fills the role of a weight. Whenthe reader is mounted on the stand, since the center of gravity of thestand can be lowered, the stand becomes stable.

A part A of the plate 611 is molded in line with the shape of the base61 of the stand 2. Normally, the plate 611 will not come out of thestand 2. The plate 611 and stand 2 are secured with two screws. A screwhole used to fix the plate and bored in the stand is shown even in thefront sectional view of FIG. 21.

The plate has three holes along the same line. In the state shown inFIG. 24, that is, in a normal state, a hole c in the center of the platecoincides with the position of a screw hold 601 in the stand base. Twoscrew holes are formed intermediately between the center hole c and ahole a in the plate.

For hanging the stand on a wall, as shown in FIG. 25, the plate isturned upside down relative to the state shown in FIG. 24. An upper viewin FIG. 25 is a view of the back side of the plate, and a lower viewtherein is a view of the lateral side thereof. In this state, the hole aof the plate coincides with the screw hole of the stand base. The hole bof the plate comes out of the stand.

For hanging the stand on a wall, the hole b of the plate and the hole ofthe stand base (hole a of the plate) are used to attach screws. Thestand is thus fixed to the wall. FIG. 26 is an oblique view showing thework of attachment. FIG. 27 is a side sectional view showing the stand 2in a state in which the stand 2 is hung on a wall 150. As shown in thesedrawings, in this embodiment, the stand is screwed at two points. Thestand will not rotate when hung on a wall. Moreover, the work ofscrewing the plate can proceed smoothly.

Without a mechanism for stopping the pivoting of the holder section,there is a possibility that when the reader is angled even slightly, itis turned to the position a in FIG. 23 because of the weight of thereader and other factors. The stand in this embodiment is thereforeprovided with a mechanism for controlling the pivoting of the holdersection in a multistage fashion and for stopping the pivoting of theholder section.

FIG. 28 is an explanatory view concerning a tilt mechanism. FIG. 29 is aside perspective view showing the major portion of the stand having thetilt mechanism in enlarged form. FIG. 30 is a front view of the majorportion. A supporting member 622 having a plurality of teeth in an arcform is fixed to the base of the stand. A spring 623 is located at oneof the fulcrums of the holder section. The other end of the spring isattached to a locking member 624 that is shaped to mesh with the teethof the supporting member fixed to the base. The locking member isconstrained to go toward the fulcrum because of the elasticity of thespring.

Since the tilt mechanism is employed in the stand, when the holdersection is pivoted, the teeth of the supporting member are meshed withthe teeth of the locking member. The supporting member is constrained togo toward the fulcrum due to the elasticity of the spring. The holdersection 62 can therefore be locked in a pivoted state. Consequently, amulti-stage angle adjustment can be realized.

FIG. 29 shows the cable 3 led out from the bottom of the reader. Thecable is bent toward the read-window side of the reader so that thecable can be led out to the user side without fail when the reader ismounted on the stand.

As mentioned above, when the reader is mounted on the stand, the readercan be used as a stationary reader. If necessary, the reader can bedismounted from the stand and used as a hand-held reader.

For using the reader as a hand-held reader, a user holds the grip 12.When the reader is mounted on the stand, the grip of the reader isinserted into the holder section. For dismounting the reader from thestand, it is impossible to hold the grip and dismount the reader. Unlesshands are changed, the grip cannot be held. For dismounting the readerfrom the stand, the head must be held. The head is larger than the gripand hard to hold with a hand. Especially, a user having small hands maynot be able to raise the head with one hand. Thus, there is a problemthat the work of dismounting the reader from the stand is troublesome.

In order to solve this problem, the grip is designed to be held with thereader mounted on the stand.

FIG. 31 shows a stand proposed to solve the problem. In FIG. 31, alaying stand 64 is attached to the stand that has been described so far.The laying stand has a tongue 65 on the bottom thereof. The tongue isinserted into the holder section. The laying stand 64 is attachable anddetachable to and from the stand body. When needed (for laying thereader), the laying stand is attached to the stand body. When not needed(for erecting the reader), the laying stand is detached from the standbody.

FIG. 32 is a view showing a state in which the reader is mounted on thelaying stand. The reader 1 is laid on the laying stand shown in FIGS. 31and 32. Specifically, the head 11 of the reader 1 is placed on thelaying stand. Even in this case, no special mechanism is needed in orderto fix the head of the reader to the laying stand. The reader 1 ismerely locked on the laying stand owing to its own weight.

However, when the reader is laid, the grip comes out sideways. Thereader cannot be laid on the laying stand on a stable manner when nomeasure is taken. The laying stand is therefore provided with threewalls 641, 642, and 643 for supporting the head. The right and leftwalls 641 and 642 of the laying stand support the lateral side of thehead 11 of the reader ad part of the front side of the head 11. The wall643 formed at the deep end of the laying stand supports the back side ofthe head 11 of the reader. Owing to these walls, the orientation of thefirst read window 13 a of the reader is defined. The first read windowcan be directed toward the user side. Furthermore, it can be preventedthat the reader falls off the laying stand.

In FIG. 32, the grip of the reader is located on the right hand. Thus,the grip is not inserted into the stand but comes out of the stand. Auser can therefore hold the grip readily. The reader can be dismountedfrom the stand with the grip thereof held.

The laying stand has a symmetric shape. As shown in FIGS. 33A and 33B,the grip can be placed on either the right or left hand. FIG. 33A showsa state in which the grip is placed on the left hand (relative to auser). FIG. 33B shows a state in which the grip is placed on the righthand (relative to a user). FIG. 33B shows the walls supporting the frontside of the head, while FIG. 33A does not show the walls for betterunderstanding of the state of the head on the laying stand.

As shown in FIGS. 33A and 33B, the grip 12 of the reader 1 can be placedon either the right or left hand. Depending on whether a user isright-handed or left-handed, the orientation of the grip of the readerthat is laid on the stand can be selected freely.

When intending to have a bar code read, a user tends to pass the barcode intentionally horizontally or vertically by the read windowemployed. Moreover, a bar code is printed lengthwise on, for example, acan. Thus, in many cases, the width or length direction of an articlebearing a bar code agrees with the longitudinal direction of the barcode. It may be a matter of course in terms of the user's way ofmaneuvering the reader that the probability that the orientation of abar code passing the read window is a horizontal or vertical directionis high.

when the reader is used as a stationary reader in order to read a barcode, although the angle of the bar code need not concern the user, itis preferable in consideration of the aforesaid point that the scanningpattern supplied from the read window employed includes a substantiallyhorizontal or vertical scanning ray.

When the reader is mounted on the laying stand, it is angled so that atleast one scanning ray constituting the scanning pattern supplied fromthe first read window scans horizontally. More particularly, as shown inFIGS. 33A and 33B, the reader is placed so that the grip 12 of thereader 1 slightly slants down. When the reader is angled this way, oneof scanning rays constituting the scanning pattern is scannedhorizontally.

Likewise, the reader is placed so that one of the scanning raysconstituting the scanning pattern supplied through the first read window13 a is scanned vertically.

Since the scanning pattern thus includes horizontal and verticalscanning rays, the horizontal or vertical orientations of bar codes,with which the bar codes are passed at a high probability, agree withthe scan directions of the scanning rays. Reading bar codes can beachieved more reliably.

FIGS. 34 and 35 are views showing the reader erected on the stand incomparison with the reader laid on the stand. FIG. 34 shows an erectingstand, while the FIG. 35 shows a laying stand.

As shown in FIG. 34, when the erecting stand is used, the grip 12 isinserted into the holder section. The reader mounted on the stand isstable. However, it is hard to dismount the reader from the stand byholding the grip. The work of mounting or dismounting the reader israther hard to do.

As shown in FIG. 35, when the laying stand is used, since the grip ofthe reader is easy to hold, the work of mounting or dismounting thereader can be carried out efficiently. In particular, when the reader isused as a hand-held reader, it becomes unnecessary to change hands.However, since the grip is coming out sideways, it is hard to balancethe weight of the reader. The reader mounted on the stand does notbecome stable immediately.

A user is therefore requested to select the erecting stand or layingstand by taking account of the usage of the reader and the merits anddemerits of the stands.

When the reader is used as a stationary reader or gun reader, thescanning pattern supplied through the first read window 13 a is used toperform multi-scan. The scanning light emitted through the second readwindow 13 b is not directly involved in reading of bar codes.

As shown in FIGS. 9 and 14, the supply direction of the scanning patternthrough the first read window 13 a is different (has a different angle)from the emission direction of the scanning light through the secondread window 13 b. If scanning light is emitted through both the firstand second read windows, in case the reader is used as a stationary orgun reader, when the scanning pattern supplied through the first readwindow is directed toward a bar code that is an object of reading, thescanning light emitted through the second read window travels in adirection completely different from the direction toward the bar codethat is an object of reading, and therefore scans something that has notrelation to the bar code.

There is a possibility that light reflected from anything other than abar code that is an object of reading, which has been scanned by thescanning ray emitted through the second read window, may be detected bythe reader. This results in noise or incorrect recognition by thereader. In this case, the reader causes a read error.

By contrast, when the reader is used as a touch reader, the scanningpattern supplied through the first read window is not used for bar-codereading. However, as shown in FIG. 13C, even when the scanning rayemitted through the second read window is used to read a bar code on abar-code menu, if scanning rays are still emitted through the first readwindow, a bar code that is not an object of reading is scanned by thescanning rays emitted through the first read window. The reader thendetects both reflected light of the scanning rays emitted through thefirst read window and reflected light of the scanning rays emittedthrough the second read window.

In case the both kinds of reflected light contain bar-code data that isvalid data, the reader cannot distinguish which is wanted data. Inparticular, since all bar codes recorded on a bar-code menu are validdata irrespective of whether the data is or is not required to be input,two different bar codes coexist. This leads to a problem that doublebar-code read occurs. In this case, since it is impossible to input therequired information alone, the input information must be erased or datamust be input again.

In order to solve the foregoing problem, according to a read form of thereader, it is required to substantially invalidate bar-code readingbased on scanning light emitted through a read window not associatedwith the read form during, for example, a period during which thescanning light is emitted through the read window not associated withthe read form.

FIG. 36 is a view showing part of a polygon mirror. A structure for usein locating a position scanned by a scanning ray is shown. A disk-likemember 222 having a plurality of slits is placed on the base of thepolygon mirror 22. A sensor 221 for detecting the passage of a slit ismounted on the base on which the polygon mirror is placed. Whendetecting passage of a slit, the sensor 221 outputs a mirror positiondetection signal.

One of the slits formed on the disk member 222 has a larger width inorder to indicate a reference polygon position. The sensor is used todetect the slit indicating the positional reference, whereby a controlunit of the reader, which is not shown, recognizes that a specificsurface of the polygon mirror has passed the sensor position. Thus, thecontrol unit grasps the rotated state of the polygon mirror, and judgesto which floor mirror scanning light is incident.

When the reference position is set to a specific position of the polygonmirror, it can be recognized that the specific position of the polygonmirror has passed the sensor position. By counting the number of slitspassed after the detection of the reference position, it can be checkedreadily which surface of the polygon mirror has passed the sensorposition.

FIG. 37 shows the waveform of an output of the sensor shown in FIG. 36and the waveform of a mirror position detection signal based on theoutput. FIG. 37 shows the sensor output and mirror position detectionsignal. In FIG. 37, (1) is associated with the first reflection surface,(2) is associated with the second reflection surface, (3) is associatedwith the third reflection surface, and (4) is associated with the fourthreflection surface.

Furthermore, in FIG. 37, reference numerals 23-1 to 23-8 denote thefloor mirrors to which scanning light reflected from the respectivereflection surfaces is incident and which correspond to the floormirrors shown in FIG. 7A. Herein, although “23-1 to 23-5” is written inFIG. 37, when the polygon mirror is rotating clockwise in FIG. 7A, theactual scanning order is the floor mirrors 23-3, 23-2, 23-1, 23-5, and23-4.

The sensor output shown in FIG. 17 is driven on every time a slit isdetected, and driven off for the other things. The duration during whichthe output is on is comparable to the width of a slit. As shown in FIG.37, the wide slit serving as a positional reference is formed so that itwill be detected when scanning light reflected from the first reflectionsurface starts scanning the floor mirrors 23-1 to 23-5 (actually thefloor mirror 23-3).

When the wide slit is detected, the on duration of the sensor output islong. The control unit of the reader which is not shown recognizes thatthe scanning light reflected from the first reflection surface of thepolygon mirror has started scanning the floor mirror 23-3.

The number of slits formed on the disk member is predetermined. It isalso predetermined which slit is associated with which position of whichreflection surface of the polygon mirror. Once the positionalrelationships of the reference slit passing the sensor with thereflection surfaces of the polygon mirror are pre-set in the controlunit or the like, the control unit can readily grasp which reflectionsurface of the polygon mirror is reflecting light and which floor mirroris being scanned by the reflected light by counting the number of slitsthat have passed the sensor after the detection of the reference slit.The control unit then recognizes the period during which scanning lightreflecting from the fourth reflection surface of the polygon mirror isscanning the floor mirror E8, and, as shown in FIG. 37, retains themirror position detection signal in the one state during the period.

FIG. 38 is a functional block diagram of the reader. In FIG. 38,reference numeral 221 denotes a sensor mounted on the base of thepolygon mirror. The sensor 221 detects a slit 223. 225 denotes a controlunit for controlling the operations of the reader. 226 denotes a counterfor counting the number of outputs of the sensor 221. 21 denotes a laserdiode serving as a light source. 227 denotes a light detection circuitfor detecting light reflected from a bar code. The operations of thelaser diode 21 and light detection circuit 227 are controlled by thecontrol unit 225.

Furthermore, reference numeral 224 denotes a mode selection switch. Thereader has two read modes: a first read mode (multi-scanning mode) inwhich a scanning pattern composed of a plurality of scanning raysemitted through the first read window is supplied, and a second readmode (single-scanning mode) in which one scanning ray is emitted throughthe second read window. A user manipulates the mode selection switchwhen he/she needs it, whereby the first read mode and second read modecan be changed. Thus, the user can designate a desired read mode.

FIG. 39 is a flowchart describing read mode change achieved bymanipulating the mode selection switch. The control unit always monitorsif the mode selection switch has been manipulated (step 901). When themode selection switch is not manipulated, the read mode is regarded asthe multi-scanning mode (step 903) and the light source is controlled sothat scanning light will be emitted through the first read window.

In contrast, when it is detected that the mode selection switch has beenmanipulated, the control unit changes the read mode into thesingle-scanning mode and controls lighting of the light source so thatscanning light will be emitted through the second read window alone(step 902).

Based on the thus-selected read mode, bar-code reading is executed.

FIG. 40 is a flowchart describing how to control lighting of the lightsource more particularly.

What is needed in multi-scanning mode is scanning light emitted throughthe first read window 13 a. Scanning light reflected from the floormirror 23-8 is not needed to read bar codes. By contrast, what is neededin single-scanning mode is only the scanning light emitted through thesecond read window 13 b. Only the scanning light reflected from thefloor mirror 23-8 is needed and the other scanning light is not needed.

When the read mode is set to single-scanning, the control unit operatesthe laser light source only during a period during which light reflectedfrom the polygon mirror is scanning the floor mirror 23-8 (step 907),and reads a bar code. By contrast, when the read mode is set to themulti-scanning mode, the control unit does not operate the laser lightsource during a period during which the floor mirror 23-8 is scanned(step 908), and reads a bar code.

Owing to the foregoing lighting control, scanning light can be emittedonly through the read window associated with each read mode.

FIG. 41 shows the waveforms of outputs of the components shown in FIG.38.

An output from the mode selection switch is fed to the control unit. Forselecting the first read mode (for emitting scanning light through thefirst read window 13 a), the output is driven off. For selecting thesecond read window 13 b), the output is driven on. The control unitchecks the output of the mode selection switch to see which read mode isselected. Depending on the result, the control unit controls lighting ofthe laser diode.

The mirror position detection signal is identical to the one shown inFIG. 37, and remains on during a period during which light reflectedfrom the fourth surface of the polygon mirror is scanning the floormirror 23-8.

During a period during which the mode selection switch remains onbecause a user intends to use the reader in second read mode or as atouch reader, scanning light is emitted through the second read window13 b but scanning light must not be emitted through the first readwindow 13 a. For a period during which the mirror position detectionsignal remains on, the control unit gives control so as to light thelaser light source. For a period during which the mirror positiondetection signal remains off (the floor mirrors 23-1 to 23-7 are beingscanned), the control unit gives control so as not to operate the laserlight source. Thus, laser light is emitted only through the second readwindow 13 b. When the reader is used as a touch reader in order to reada bar-code menu, it can be prevented that scanning light emitted throughthe first read window scans an unrelated bar code to cause a doubleread.

When a user uses the reader as a stationary or gun reader, the output ofthe mode selection switch is driven off. Based on this fact, for aperiod during which the mirror position detection signal remains off,the control unit operates the laser light source. For a period duringwhich the mirror position detection signal remains on (scanning lightreflected from the fourth reflection surface of the polygon mirror isscanning the floor mirror 23-8), the control unit does not operate thelaser light source.

Owing to the foregoing control, even when the reader is used as astationary or gun reader, it can be prevented that scanning light isemitted through the second read window 13 b. It can be prevented thatany unrelated thing other than a bar code is scanned.

FIG. 42 is a view showing an example of a mode selection switch. FIG. 42shows the back side of the reader. The reader of the embodiment shown inFIG. 42 has a mode selection switch 15 d on the back side thereof. Themode selection switch 15 d is manipulated by the index finger or thumbof a user's hand holding the grip.

It is required to form the mode selection switch at a positionpermitting easy manipulation by a finger of a hand holding the grip. Inparticular, either a person having large hands or a person having smallhands must be able to manipulate the mode selection switch in the samemanner.

The mode selection switch is formed even on, for example, the readershown in FIG. 15. In the case shown FIG. 15, the mode selection switch15 b is shaped like a letter V. Owing to the shape like a letter V, themode selection switch can be made long and wide.

The position on the switch at which the finger is rested variesdepending on whether the switch is manipulated by an index finger or bya thumb. However, since the mode selection switch is made long, eitherthe index finger or thumb can press the mode selection switch. Since themode selection switch is made wide, either a person having long fingersor a person having short fingers can manipulate the mode selectionswitch in the same manner.

FIG. 43 is a view showing a state in which the mode selection switch(function change switch) is pressed by an index finger. In this case, auser holds the grip with all his/her fingers except the index finger andstretches the index finger. The mode selection switch is located at aposition at which the stretched index finger lies.

When the grip is held as shown in FIG. 43, the index finger and thumb ofa maneuvering person is spaced like a letter V, though it depends on theperson. When the grip is held by a right hand, the index finger lies onthe right-hand part of the mode selection switch. When the grip is heldby a left hand, the index finger lies on the left-hand part of the modeselection switch. Since the mode selection switch is made wide, as shownin FIG. 43, when the grip is held, the index finger can be rested on themode selection switch in a natural manner. Furthermore, whichever of aright hand and left hand is used, the mode selection switch can bemanipulated in the same manner.

FIG. 44 is a view showing a state in which the mode selection switch(function change switch) is manipulated by a thumb. In this case, thegrip is held by all the fingers except the thumb and the root of thethumb.

When a thumb is used to manipulate the mode selection switch, the thumbmanipulates the root of the mode selection switch mainly.

As mentioned above, the position of the finger varies depending onwhether an index finger is used to manipulate the mode selection switchor a thumb is used thereto. Since the mode selection switch is madelong, the switch can be used for switching by an index finger or by athumb. Since the mode selection switch is shaped like a letter V, theswitch can be pressed reliably in whatever manner it is manipulated.

FIGS. 45A and 45B are views showing a V-shaped switch plate. The switchplate shown in FIGS. 45A and 45B is supported at three points. Threefulcrums; fulcrums A, B, and C are set at the apices of the switchplate. The apices serving as the fulcrums are inserted into openings,which are not shown, formed in the back side of the reader, and thensupported by juts in the openings. A claw is formed at the tip of eachapex serving as a fulcrum. The claws prevent floating of each apexserving as a fulcrum.

A switch is incorporated in an area of the reader body coincident withthe center of the switch plate. When the switch plate is manipulated,the switch is depressed. Whichever position of the switch plate ismanipulated, the depressing section of the switch incorporated in thereader body can be depressed. Unlike a structure in which a switch liesat only one point, even a person having small hands will find it easy tomanipulate the switch. The switch plate is constrained to go slightlyupward by means of a spring or the like within the switch.

FIGS. 46A and 46B are diagrams for explaining the operation of theswitch plate. Herein, letters A, B, and C denote fulcrums shown in FIGS.45A and 45B. The outline of the switch plate is not shown.

FIG. 46A shows a state in which a portion of the switch plate in thevicinity of fulcrum A is manipulated, and FIG. 46B shows a state inwhich a portion of the switch plate in the vicinity of fulcrum B ismanipulated. When the portion of the switch plate in the vicinity offulcrum A is manipulated, the apices serving as fulcrums B and C arefixed. A straight line linking the apices of fulcrums B and C acts as apivot of the switching plate. When the portion of the switch plate inthe vicinity of fulcrum A is manipulated, the switch plate is presseddown with the line linking the apices of fulcrums B and C as a pivot.Thus, the switch is depressed.

Likewise, when the portion of the switch plate in the vicinity offulcrum B is manipulated, the apices of fulcrums A and C are fixed. Thestraight line linking the apices of fulcrums A and C acts as a pivot ofthe switch plate. The switch plate is pressed down, and the switch isthus depressed.

As mentioned above, since the switch plate is attached, whicheverportion of the switch plate is manipulated, the switch can be depressed.The mode selection switch can be manipulated in a stable mannerirrespective of the size of a user's hand. The number of fulcrums neednot be three. However, when three fulcrums are set, a pivot (rotationaxis) relative to a pressed point can be determined uniquely. Foractuating the switch most reliably, the structure of the switch platehaving three fulcrums is most effective.

The switch plate is attached to the reader so that it will not come outof the back side of the reader. If the switch plate jutted out of theback side of the reader, there would arise a possibility that when thereader is placed on a tabletop with the back side thereof facing down,the read mode of the reader is changed to one not intended by a user.

FIG. 47 is a view showing another function change switch. In the caseshown in FIG. 47, a change switch 15 e for front-side manipulation islocated in the vicinity of the root of the grip. The position of theswitch is a position at which an index finger lies when the grip is heldby a hand. The front-side change switch can therefore be manipulated bythe index finger. In particular, the shape of the switch makes itpossible to form the switch at almost the same position as the triggerswitch 15 a of the gun reader shown in FIG. 3. The change switch can bemanipulated easily.

In the case shown in FIG. 47, the mode selection switch on the back sideof the read may be omitted. However, the mode selection switch may ofcourse be formed on each of the back side and front side of the reader.

FIG. 48 is a view showing yet another example of a change switch. In thecase shown in FIG. 48, side switches are formed on the lateral sides ofthe head of the reader. The side switches are a side switch 15 f locatedon the left-hand side of the reader and a side switch 15 g located onthe right-hand side thereof.

When the grip is held by a hand, the thumb and index finger can berested on the side switches. When the grip is held by a right hand, thethumb is used to manipulate the side switch 15 f and the index finger isused to manipulate the side switch 15 g. The grip is held by theremaining fingers. When the grip is held by a left hand, the thumb andindex finger are used to manipulate the opposite switches. Thus, inconsideration of the uses of both the right and left hands formanipulation of a switch, the side switches are located on the lateralsides of the reader respectively. Owing to this layout, the two switchescan be manipulated simultaneously with ease. Needless to say, only oneof the side switches may be manipulated.

In the case of the reader shown in FIG. 48, since the side switches arelocated on both the lateral sides of the reader. In an effort to makethe most of this structure, the functions of the side switches may bevaried depending on whether one of the side switches is manipulated toboth thereof are manipulated simultaneously.

When one of the side switches is manipulated, the side switch acts as amode selection switch. In this case, it does not count whichever of theside switches is manipulated.

When both the side switches is manipulated simultaneously, the sideswitches do not act as mode selection switches but are assignedcompletely different functions.

For example, when one of the right and left side switches is manipulated(it does not count whichever of the side switches is manipulated), theread mode is changed from one to the other. When the right and left sideswitches are manipulated simultaneously, special reading, for example,repetitive input of a product to be read is executed.

The control unit of the reader always monitors the manipulationsituations of the right and left side switches, judges whether both theright and left side switches are manipulated simultaneously or one ofthe side switches is manipulated, and selects processing to be executedon the basis of the result of the judgment.

In case a plurality of bar codes representing the same kind of contentsare read, for example, when a plurality of articles are registered at atime, it is time-consuming to read the bar codes one by one. A readerhaving a repetitive input function is known.

For using the repetitive input function, first, a bar code is read. Inprinciple, a repeat input key is manipulated by the number of articlesof which bar codes must be input. The repeat input key acts as a counterkey. The frequency of manipulating the key is counted by the reader,whereby it is judged how many articles are of the same product.

Using the foregoing repetitive input function, bar codes borne byarticles of the same product need not be read one by one.

In this embodiment, two kinds of function can be assigned to the sideswitches by distinguishing simultaneous manipulation of two sideswitches from manipulation of one of the side switches. That is to say,the functions of the side switches are varied depending on whether oneof the side switches is manipulated or both thereof are manipulatedsimultaneously. Thus, the functions of switches such as the capabilitiesof the repeat input key and mode selection switch can be changedaccording to the number of the switches that have been manipulated. Thisleads to a reduction in number of switches or keys.

For executing reading according to a read mode, herein, read modes arechanged by controlling lighting of the laser light source in such amanner that when scanning light is emitted through the first read window13 a, scanning light is not emitted through the second read window 13 b,and that when scanning light is emitted through the second read window13 b, scanning light is not emitted through the first read window 13 a.However, read mode change is not limited to this method.

FIG. 49 is a diagram for explaining read mode change according toanother method. FIG. 49 shows an output of the mode selection switch, amirror position detection signal, and a light detection circuit controlsignal used to control the light detection circuit and sent from thecontrol unit. Even in the case shown in FIG. 49, the internal componentsof the reader are identical to those shown in FIG. 38. Locating a scanposition is carried out by means of the structure shown in FIGS. 36 and37; that is, by counting the number of slits formed on the disk member.

The light detection circuit control signal is a signal used to controlwhether the light detection circuit should be actuated or halted. Duringa period during which the light detection circuit control signal remainson, the light detection circuit operates. During a period during whichthe light detection circuit control signal remains off, the lightdetection circuit does not operate.

In the case shown in FIG. 49, when the mode selection switch is used toselect the window 13 b; that is, the single-scanning mode, the controlunit drives the light detection circuit control signal on for a periodduring which the mirror position detection signal remains on, and drivesthe light detection circuit control signal off for a period during whichthe mirror position detection signal remains off. When thesingle-scanning mode is selected, therefore, the operation of the lightdetection circuit is validated only for a period during which scanninglight is being emitted through the second read window 13 b, andinvalidated for the other periods.

In single-scanning mode, therefore, even if scanning light is emittedthrough the first read window 13 a, the light detection circuit does notreceive light reflected from a bar code or the like. Even if a bar codeother than a specific bar code that is an object of reading is scannedduring the period, a reading operation is scanned during the period, areading operation is substantially invalidated. During the period duringwhich scanning light is being emitted through the second read window 13b, the operation of the light detection circuit is valid. Bar-codereading is therefore enabled.

By contrast, in multi-scanning mode, the output of the mode selectionswitch is off. Based on this fact, the control unit drives the lightdetection circuit control signal on for a period during which the mirrorposition detection signal remains off, and thus validates the operationof the light detection circuit. For a period during which the mirrorposition detection signal remains on, the control unit drives the lightdetection circuit control signal off and thus invalidates the operationof the light detection circuit.

For a period during which scanning light is emitted through the firstread window, therefore, the operation of the light detection circuit isvalidated and bar-code reading is enabled. For a period during whichscanning light is being emitted through the second read window, theoperation of the light detection circuit is invalidated. Although thescanning light is emitted through the second read window, the lightdetection circuit does not receive reflected light.

FIG. 50 is a diagram describing the foregoing control in the form of aflowchart. The control unit first judges a designated read mode (step911). When the single-scanning mode is selected, the light detectioncircuit is allowed to operate during a period during which the floormirror 23-8 is being scanned. In contrast, when the multi-scanning modeis selected, the control unit does not allow the light detection circuitto operate during the period during which the floor mirror 23-8 is beingscanned, but allows the light detection circuit to operate during aperiod during which any other floor mirror is being scanned (step 913).

As mentioned above, when the control operation described in FIGS. 49 and50 is carried out, even if control is not given to operating the laserdiode, a bar-code reading operation can be substantially invalidated fora period during which scanning light is emitted through a read windownot associated with a read mode.

Changing validation of the operation of the light detection circuit intoinvalidation thereof or vice versa may be achieved by changing theoperation of the light receiving device from one to the other or byinvalidating the operation of a circuit for processing a signal outputfrom the light receiving device. Incidentally, read data is decodedwithin the reader. Validation of a decoding operation may be changedinto invalidation thereof or vice versa.

FIG. 51 is a flowchart describing controlling of the state of a decodingcircuit according to a scanning situation. In the case shown in FIG. 51,when determining that the read mode is the single-scanning mode, thecontrol unit allows the decoding circuit to operate during a periodduring which the floor mirror 23-8 is being scanned and to halt duringany other period (step 917).

By contrast, when determining that the multi-scanning mode has beenselected, the control unit invalidates the operation of the decodingcircuit for the period during which the floor mirror 23-8 is beingscanned, and validates it during any other period (step 918).

Alternatively, changing validation of the light detection circuit or thelike into invalidation thereof or vice versa and controlling lighting orputting out of the laser diode may be effected in combination. Thismakes it possible to prevent emission of scanning light through a windownot associated with a read mode and to prevent extraneous light enteringthrough a read window during the period from being detected by the lightdetection circuit. Consequently, a read mode change operation can becarried out more reliably.

FIG. 52 is a diagram showing another arrangement for executing read modechange. In the case shown in FIG. 52, a mirror corresponding to thefloor mirror 23-8 is not included. The angle of one floor mirror 23-1′(corresponding to the floor mirror 23-1 in FIG. 7) is made variabledepending on the operation of a solenoid 28.

The solenoid 28 is movable right and left in FIG. 52, and has an arm atthe tip thereof. The arm is provided with the floor mirror 23-1′. Theangle of the floor mirror 23-1′ is therefore varied with the right orleft movement of the solenoid 28.

When the floor mirror 23-1′ lies at a first position (indicated withsolid lines in FIG. 52), scanning light reflected from the floor mirror23-1′ is emitted through the first read window 13 a. By contrast, whenthe floor mirror 23-1′ lies at a second position (indicated with dashedlines in FIG. 52), scanning light reflected from the floor mirror 23-1′is emitted through the second read window 13 b.

When the reader is used as a stationary or gun reader, the floor mirroris set at the first position. When the reader is used as a touch reader,the floor mirror 23-1′ is set at the second position. Controllingpositioning of the floor mirror 23-1′ is performed with the manipulationof the mode selection switch 13 b.

When the output of the mode selection switch is on; that is, when thesingle-scanning mode is selected, the control unit actuates the solenoid28 so as to move the floor mirror 23-1′ to the first position. When theoutput of the mode selection switch is off; that is, when themulti-scanning mode is selected, the control unit actuates the solenoidaccordingly so as to move the floor mirror 23-1′ to the first position.

Owing to the foregoing arrangement, in multi-scanning mode, scanninglight is not emitted through the second read window 13 b. However, insingle-scanning mode, scanning light is emitted through not only thesecond read window 13 b but also the first read window 13 a. When thesingle-scanning mode is selected, therefore, it is required toinvalidate a bar-code reading operation for a period during whichscanning light is being emitted through the first read window.

FIG. 53 is a diagram showing the waveforms of signals used for the abovecontrol. In FIG. 53, an output of the mode selection switch is identicalto the one shown in FIG. 41 or 49. A mirror position detection signalremains on during a period during which light reflected from areflection surface of the polygon mirror is scanning the floor mirror23-1′, and remains off during any other period during which any otherfloor mirror is being scanned. In this case, the period during which themirror position detection signal remains on may be limited to a periodassociated with any specific reflection surface or may be any of periodsassociated with a plurality of reflection surfaces. In the case shown inFIG. 53, the mirror position detection signal remains on only whilelight reflected from one specific reflection surface of the polygonmirror is scanning the floor mirror 23-1′.

A light source control signal is sued to control lighting of the laserlight source. When the signal is driven on, the laser light source islit. When it is driven off, the laser light source is put out.

In the case shown in FIG. 53, when the multi-scanning mode is selected(the output of the mode selection switch is driven off), the laser lightsource is lit irrespective of the scan position of light reflected fromthe polygon mirror. In contrast, when the single-scanning mode isselected, the light source control signal is driven on for a periodduring which the mirror position detection signal remains on; that is,the floor mirror 23-1′ is being scanned. The laser light source is thuslit. For any other period, the light source control signal is drivenoff, and thus the laser light source is put out.

FIG. 54 is a flowchart describing the foregoing control. When adesignated read mode is the single-scanning mode, the control unitdrives the solenoid so as to move the floor mirror 23-1′ to position b(step 922). For only the period during which the floor mirror 23-1′ isbeing scanned, is the laser light source lit (step 923).

By contrast, when the multi-scanning mode is selected, the control unitdrives the solenoid so as to move the floor mirror 23-1′ to position a(step 924). Thus, the laser light source is lit all the time (step 925).

As mentioned above, the arrangement shown in FIG. 52 is used to give thecontrol described in FIGS. 53 and 54. In multi-scanning mode, therefore,scanning light is emitted only through the first read window 13 a. Insingle-scanning mode, scanning light is emitted only through the secondread window 13 b. Only for a period during which scanning light is beingemitted through a read window associated with a read mode, is a readingoperation validated. Consequently, incorrect detection of noise ordouble reading can be prevented.

In the case shown in FIG. 52, operation of the light source iscontrolled. In the reader having the arrangement shown in FIG. 52,validation and invalidation of the light detection circuit or ofdecoding may be changed.

FIG. 55 is a view showing a state in which the reader is placed directlyon a tabletop (without the use of the stand). In FIG. 55, the reader islaid on the tabletop. As seen from the top view in FIG. 15, the lateralsides of the head of the reader are chamfered obliquely. When the readeris placed on a tabletop, the read window employed faces obliquely up byan angle corresponding to the angulation of the lateral sides of thereader. A bar-code read area is therefore located obliquely above thereader.

When the reader is placed on a tabletop, articles bearing bar codes thatare objects of reading pass above the reader. The read window employedis therefore directed upward so that a read area will be locatedobliquely above the reader. Thus, the read area is set in the vicinityof the positions of passing articles. Thus, the maneuver for bar-codereading can be achieved easily.

By contrast, if the read window faces substantially horizontally, partof a scan range covered by scanning light would be intercepted by thetabletop. This poses a problem that the scan range becomes substantiallynarrow. Moreover, since bar codes must be passed a position very closeto the tabletop, the maneuverability for reading deteriorates.

As mentioned above, when the reader is placed on a tabletop without theuse of the stand or the like, the read window employed is directedobliquely upward so that scanning light will be emitted upward. Thus,the maneuverability for reading can be improved.

When the reader shown in FIG. 55 is used as a hand-held reader,similarly to when the laying stand shown in FIGS. 33A and 33B is used,the grip of the reader can be held readily. Hands need not be changed inorder to grasp the reader. In the case of the reader shown in FIG. 55,especially, since the stand is unnecessary, both the capabilities of astationary reader and hand-held reader can be realized using the onereader.

When the reader is placed on a tabletop like the reader shown in FIG.55, the multi-scanning mode is executed in principle. When the reader isplaced on a tabletop, one of the lateral sides of the reader is incontact with the tabletop. This nature of the reader is utilized inorder to change read modes automatically.

FIG. 56 is a view showing a reader having mode detection sensors on thelateral sides thereof. As shown in FIG. 56, the mode detection sensorsare placed one by one on the lateral sides of the reader. The modedetections sensors may be, for example, optical sensors for detecting aquantity of incident light.

FIG. 57 shows a state in which the reader having the mode detectionsensors which is shown in FIG. 56 is placed on a tabletop. The reader isfundamentally identical to the one shown in FIG. 55 except the presenceof the mode detection sensors. In the case of the reader shown in FIG.57, the reader is placed on the tabletop so that the right-hand side (onthe side of the mode detection sensor 17L) of the reader with respect tothe front side of the reader will be the top side.

In the state shown in FIG. 57, extraneous light enters the modedetection sensor L. The quantity of light incident to the mode detectionsensor 17L does not decrease. By contrast, the mode detection sensor 17R(not shown) is in contact with the tabletop. The quantity of lightincident to the mode detection sensor 17R decreases compared with thatincident to the mode detection sensor L. By utilizing the relationshipbetween the state of the reader and the quantities of light incident tothe mode detection sensors, the read mode is changed into a read modesuitable for the state of the reader on the basis of the quantities oflight incident to the mode detection sensors.

FIG. 58 is a flowchart describing control of read mode change using themode detection sensors.

The control unit judges on the basis of the quantities of light incidentto two mode detection sensors if the reader is placed on a tabletop(step 931). When it is judged that the reader has been placed on thetabletop (the quantity of light incident to one of the light detectionsensors decreases), the reader is changed into the multi-scanning mode(step 933). When the quantities of light incident to the mode detectionsensors remain unchanged, the control unit changes the reader into thesingle-scanning mode (step 932).

As mentioned above, read modes are changed automatically according towhether the reader is placed on a tabletop or it is not placed thereon(used as a hand-held reader). This obviates the necessity of forming themode selection switch on the reader.

When bar-code reading is carried out with the mode selection switch helddown, there is a possibility that a user may release the mode selectionswitch carelessly. In this case, read modes are changed, through a userdoes not intend it. In particular, when the switch is released in thecourse of the single-scanning mode that has been set in order to read abar code on a bar-code menu, if the single-scanning mode is changed intothe multi-scanning mode, there arises a fear that a bar code other thanthe bar code that is an object of reading may be read. Since theincorrectly-read bar code is proper data, the reader recognizes that acorrect bar code has been read, and reports the result to the user. Whenthe user remains unaware of the fact that read modes have been changed,if the user continues processing, incorrectly-input data is finalized asinput data.

However, owing to the operation of the mode detections sensors, sinceread modes are automatically changed according to the placed state ofthe reader, it can be prevented that a read mode is changed into anotherread mode that is not intended by a user. Consequently, incorrect inputof data can be reduced to the greatest extent.

When the reader is not placed on a tabletop, a read mode may be eitherthe multi-scanning mode or single-scanning mode. A read mode desired bya user may be selected. For example, even when the reader is used as ahand-held reader, a suitable read mode is varied depending on whetherthe reader is used as a touch reader or a gun reader. When the aforesaidmode selection switch is included in the reader having the modedetection sensors, if the reader is used as a hand-held reader, readmodes can be changed using the mode selection switch.

FIG. 59 is a flowchart describing an example of control of read modechange to be employed in the foregoing situation. When the control unitdetects that the quantities of light incident to the mode detectionsensors remain unchanged, it sets the read mode to the single-scanningmode for hand-held reading (step 942). Thereafter, the control unitmonitors if the mode selection switch has been manipulated (step 944).When the mode selection switch is not manipulated, the single-scanningmode is retained (step 946). By contrast, when a user intends to use thereader as a gun reader, if it is detected that the mode selection switchhas been manipulated, the control unit changes the read mode into themulti-scanning mode (step 945). Bar-code reading is then executed.

FIG. 60 shows a variant of the reader shown in FIG. 56. The reader shownin FIG. 60 has detection switches, which may be microswitches, in placeof the optical mode detection sensors. When the reader shown in FIG. 60is placed on a tabletop as shown in FIG. 57, the detection switch on theside of the reader in contact with the tabletop is pressed by thetabletop.

FIG. 61 is a flowchart describing control of read mode selection to beperformed in the reader shown in FIG. 60.

The control unit monitors if the mode detection switches have beendepressed (step 951). When it is judged that either of the detectionswitches has been depressed and that the reader has bee placed on atabletop, the read mode is changed into the multi-scanning mode (step953).

when it has not been detected that either of the detection switches hasbeen detected, the read mode may be set to a read mode desired by a user(for example, the multi-scanning mode is retained) in the same manner asthat in the reader shown in FIG. 51). When the multi-scanning mode isretained, it can be changed into the single-scanning mode by, forexample manipulating the mode selection switch.

Alternatively, a microswitch may be formed by the second read window 13b as described below. When the second read window 13 b is brought intocontact with a menu sheet or the like, the microswitch is turned on inorder to select the single-scanning mode.

FIG. 62 is a view for explaining a mechanism for changing the read modeinto the multi-scanning mode when the reader is erected on the stand.FIG. 63 is a flowchart describing control of read mode selection to beperformed in the reader shown in FIG. 62.

A detector (setting sensor) 121 that is a microswitch is placed on thebase of the reader. A detection jut is formed on the base of the holdersection of the stand. The position of the detection just coincides withthe position of the detector inside the reader when the reader ismounted on the stand.

When the reader is mounted on the stand, the detector in the reader ispressed by the detection jut. The control unit of the reader monitorsthe state of the detector 121 (step 951). When detecting that thedetector has been pressed, the control unit judges that the reader hasbeen mounted on the stand and changes the read mode into themulti-scanning mode (step 952).

When the detector has not been pressed, it is thought that the reader isused as a hand-held reader. In this case, the read mode may be set tothe single-scanning mode or multi-scanning mode. Whichever of the modesis selected depends on in what form a user uses the hand-held reader. Aread mode is set accordingly.

In case the reader is used as a gun reader frequently, although thereader is used as a hand-held reader, the read mode should be set to themulti-scanning mode. Changing into the single-scanning mode should beperformed with the manipulation of the mode selection switch.

On the contrary, in case the reader is used as a touch reader morefrequently, since the reader is used as a hand-held reader, the readmode should be set to the single-scanning mode. For using the reader asa gun reader, the mode selection switch is manipulated. In this case,unlike the aforesaid system design in which the read mode is changedinto the single-scanning mode with the manipulation of the modeselection switch, the control unit changes the read mode from thesingle-scanning mode to the multi-scanning mode. When the mode selectionswitch is manipulated, the control unit changes the read mode into themulti-scanning mode. When the mode selection switch is not manipulated(the reader is used as a hand-held reader), the single-scanning mode isset.

In a state in which the reader is set to the single-scanning mode, forreading a bar code on a menu sheet or the like, all bar codes locatedclose to the second read window 13 b are read. This poses a problem thatwhen the second read window 13 b approaches an intended bar code,another bar code located close by may be read. For preventing occurrenceof such a problem, as shown in FIG. 62, microswitches (window switches)181R and 181L are arranged by both edges of the second read window 13 bso that when the second read window 13 b is used to read a bar code on amenu sheet or the like, the switches 181R and 181L will be turned on.

FIG. 64 is a flowchart describing control of read mode selection to beperformed when the foregoing window switches are arranged.

If it is judged at step 961 that the single-scanning mode has beendesignated, the laser diode is turned off (step 962). It is then judgedif the window switches 181L and 181R are on (step 963). If the switchesare on, the laser diode is turned on only when the laser beam scans thefloor mirror 23-8 (step 964). A bar code is then read (step 965).

FIGS. 65A and 65B are views for explaining an arrangement for changingread modes when the reader is laid on the laying stand. FIG. 66 is aflowchart for describing read mode selection control to be given in thereader shown in FIGS. 65A and 65B.

In FIGS. 65A and 65B, an optical mark such as a bar code for instructingread mode change is formed on the inner surface of a wall 642 of all thewalls of a laying stand 64 which is opposed to the second read window.

When the reader is used as a hand-held reader, if it is presumably usedas a touch reader, it is set to the single-scanning mode. In this state,the operation of the reader is substantially invalidated for a periodduring which scanning light is emitted through the first read window.Bar-code reader is enabled only for a period during which scanning lightis emitted through the second read window.

In this state, when the reader is mounted on the laying stand, scanninglight emitted through the second read window 13 b scans a bar code 645formed inside the stand. Thus, the bar code for instructing read modechange is read.

The control unit of the reader monitors if the bar code has beendetected by light emitted through the second read window. Whenidentifying the read bar code, the control unit judges that the read barcode instructs read mode change (step 962). The control unit thenchanges the read mode from the single-scanning mode to themulti-scanning mode (step 964). Control is thus given so that bar-codereading will be valid even during the period during which scanning lightis emitted through the first read window 13 a.

When the bar code on the laying stand is not detected, the control unitretains the single-scanning mode as the read mode (step 963). Even afterthe read mode is changed into the multi-scanning mode, bar-code readingusing scanning light emitted through the second read window is stillvalid. In the state in which the reader is mounted on the laying stand,scanning light emitted through the second read window continues scanningthe bar code for instructing read mode change which is formed inside thestand.

When the reader is dismounted from the laying stand, the bar code forinstructing read mode change which is formed inside the stand is nolonger detected. Based on this fact, the control unit changes the readmode from the multi-scanning mode to the single-scanning mode.

Thus, read modes can be changed automatically according to whether thereader is mounted on or dismounted from the laying stand. For changingthe read mode into the multi-scanning mode despite the use of the readeras a hand-held reader, for example, the mode selection switch ismanipulated.

FIG. 67 is a view for explaining another mechanism for mode change. InFIG. 67, a grip sensor 122 is formed on the back side of the grip. Whena user holds the grip 12, the fact is detected by the grip sensor 122.The result of the detection is reported to the control unit. Forexample, an electrostatic sensor is used as the grip sensor 122. When aperson holds the grip, since the electrostatic capacity of the gripsensor varies, read modes are changed. Even when the grip sensor 122comes into contact with the holder section of the stand, since theelectrostatic capacity of the grip sensor does not vary, read modes arenot changed.

FIG. 68 is a flowchart describing read mode selection control to begiven in the reader shown in FIG. 67.

When it is detected owing to the grip sensor 122 that the grip 12 hasbeen held (step 966), the control unit changes read modes. In this case,the reader is thought to be used as a hand-held reader. The control unittherefore changes the read mode into the single-scanning mode on thebasis of the result of the detection (step 967).

The position of the grip sensor 122 is not limited to the back side ofthe grip. However, since it is the back side of the grip where holdingcan be checked most reliably, it is most effective to form the gripsensor at the position.

Most preferably, the aforesaid switches or sensors used to change readmodes should be formed at positions not interfering with mounting of thereader on the stand. As for the switches or sensors directly manipulatedby a user, they should be formed at positions ensuring easy manipulationfor the user.

When the reader is used as a touch reader, it is important for reliablereading to bring a bar code to scanning light emitted through the secondread window 13 b. FIG. 69 is a view showing an example of a readercapable of notifying a user of a position scanned by a scanning ray.

As already described, in a conventional touch reader, an LED is used toilluminate a bar-code surface entirely. The necessity of positioning aread window strictly is therefore low. However, in the case of thereader of this embodiment, even when the reader is used as a touchreader, a bar code is scanned with a scanning ray such as laser light.Unless the bar code is located at a position passed by the scanninglight, the bar code cannot be read. The read window employed musttherefore be positioned strictly.

The cover 14 is, as already described, attached to the perimeter of thesecond read window 13 b of the reader. Scan direction indicator marks141 indicating the start and end points of a unidirectional scanningpattern are inscribed on the right hand and left hand of the cover. Thisassists a user in checking which position is scanned by scanning light10 b emitted through the second read window. The scanning ray travelsalong a line linking the apices of the triangular marks.

The touch reader has the read window thereof approached to a bar codefor reading. In the case of the reader shown in FIG. 69, in particular,the perimeter of the second read window is shielded with the cover 14.It is hard to directly discern a bar code that is an object of reading.It is also hard to discern which position of the bar code is scanned byscanning light emitted through the second read window 13 b.

However, since the marks 141 shown in FIG. 69 are inscribed on the cover141. The scan position of a scanning ray emitted at least through thesecond read window 13 b can be judged on the basis of the marks. It cantherefore be checked indirectly which part of the bar code is beingscanned. Consequently, the bar code to be read can be read reliably.

FIG. 70 is a view showing a variant of the reader shown in FIG. 69. InFIG. 70, LED indicators 142 are formed at the positions of the scandirection indicator marks 141 shown in FIG. 69. Compared with the casein which the marks are inscribed, when the LED indicators 142 areformed, a user can discern the marks more easily and check the scanposition of scanning light more easily. The reader shown in FIG. 70 willprove effective when a place in which the reader is used is dark.

For reading a bar-code menu, when the menu sheet is placed on atabletop, the reader approaches a bar code from immediately above thebar code. If the LED indicators were formed on the back side of thereader, the LED indicators would be identified readily. However, whenthe menu sheet is held by one hand and the reader is held by the otherhand, the lateral side of the reader faces a user's face. If the LEDindicators were formed on the back side of the reader, the user wouldfind it hard to identify them. Even in this situation, as shown in FIG.70, since the LED indicators are formed on the lateral sides of thereader, the LED indicators can be discerned readily.

When the indication color of the LED indicators may be varied dependingon whether the reader is rested or used to read a bar code, thecapability of a read check indicator can be added to the LEDs shown inFIG. 70. This enables a user to check reading and a scan position ofscanning light simultaneously.

FIG. 71 is a view showing an example of another mechanism for enabling auser to recognize a scan position of scanning light emitted through thesecond read window 13 b. In the case shown in FIG. 71, projections 143indicating a position and direction to and in which scanning light isemitted are formed on both edges of the second read window. Theprojection direction of the projections 143 agrees with a direction inwhich scanning light is emitted.

The two projections 143 are brought into contact with both edges of abar code that is an object of reading, whereby scanning light emittedthrough the second read window 13 b can accurately scan the bar codethat is an object of reading. The use of such projections obviates thenecessity of bringing a bar code close to the read window employed. Itcan therefore be prevented that the bar code is hidden behind the readwindow. When a bar code is hidden behind the rear window, it cannot bechecked directly which position of the bar code is scanned by thescanning light. This problem will not occur in the reader shown in FIG.71. The state of a bar code being scanned can be discerned directly.

In the case of the reader shown in FIG. 71, a bar code that is an objectof reading through the second read window 13 b is located at the tips ofthe projections 143. Preferably, the focal position of scanning lightemitted through the second read window 13 b should therefore be presentin the vicinity of the tips of the projections.

FIG. 72 is a view sowing yet another example of a mechanism for enablinga user to identify a scan position of scanning light emitted through thesecond read window 13 b.

In the reader shown in FIG. 72, crest juts 144 are formed at both edgesof the cover formed on the perimeter of the second rear window. Thecrest juts 144 have the same significance as the marks shown in FIG. 69.Both edges of a bar code that is an object of reading are aligned withthe positions of the crest juts, whereby scanning light emitted throughthe second read window 13 b can scan the bar code reliably. Even in thecase shown in FIG. 72, it can be prevented that a bar code that is anobject of reading is hidden behind the read window.

FIG. 73 is a view for explaining a mechanism for preventing a bar codethat is an object of reading from being hidden behind the read windowemployed. In the reader shown in FIG. 73, a position at which the readwindow 13 b is formed is lowered by one step from the position shown inFIG. 70. A transparent cover 145 for properly retaining the spacingbetween the read window and a bar code is attached to the face of theread window 13 b.

Since the read window is located at a one-step lowered position, evenwhen the reader approaches a bar-code surface, the bar code can bediscerned from the back side of the reader. Since a bar code can bediscerned directly, it can be checked directly and easily which positionof the bar code is being scanned. Moreover, for reading a bar code, thebar code is brought into contact with the face of the transparent cover.Since the transparent cover 145 is attached, the spacing between a barcode and the read window can be retained properly. Consequently, it canbe prevented that discerning a bar code and checking a scan positionfrom the back side of the reader are crippled because the reader hasapproached too closely to the bar code.

When the transparent cover 145 is designed to be detachable andreplaceable, if the face of the transparent cover is flawed because itis brought into contact with a bar code, the transparent cover can bereplaced with a new one. Thus, the influence of the flaw can benullified.

FIG. 74 is a view showing reading of a bar-code menu. As shown in FIG.74, the crest juts 144 are formed on the cover on the perimeter of aread window. A proper space is interposed between a bar code and theread window (crest juts). This makes it easy to discern the bar code anda scan position.

Moreover, the back side 111 of the reader is streamlined. If the backside of the reader were angular, the angular part would interfere withdiscernment of a bar code or scan position. However, as shown in FIG.74, since the back side 111 of the reader is streamlined, even when thereader is used for hand-held reading, nothing interferes withdiscernment of a bar code or scan position. A position check can beachieved readily.

FIG. 75 is a view showing a variant of the reader shown in FIG. 74. Theback side of the reader shown in FIG. 75 has a concave part 113 formed.The formation of the concave part 113 makes it easy to check a bar codeor scan position from the back side of the reader.

FIGS. 76A and 76B are views for explaining checking of a bar-codeposition or scan position to be performed in order to read a bar-codemenu 4. The back side 111 of the reader shown in FIGS. 76A and 76B has aslope. The slope is set to have substantially the same angle as theangle of emission of scanning light emitted through the second readwindow 13 b. Since both edges of the cover 14 of the second read window13 b are formed as the juts 114, an operator's line of vision will notbe intercepted by the second read window of the reader. Consequently,the bar-code position or scan position can be checked readily by theoperator.

Scanning light emitted through the second read window 13 b travels alonga line linking the positions of scan position indicator marks 141inscribed on the lateral sides of the cover 14. When a bar code ispositioned to lie between extensions of the scan position indicatormarks 141, the bar code can be scanned reliably.

As apparent from FIG. 76A, a tip 114 of the reader is formed linearly sothat the reader can readily be aligned with the orientation of a barcode. The orientation of the tip 114 of the reader agrees with the scandirection of a scanning ray emitted through the second read window 13 b.When the orientation of a bar code is aligned with the linear tip, thebar code can be scanned thoroughly. This leads to more reliable reading.

In FIG. 76B, a scan range permitted by multi-directional scanning lightemitted through the first read window 13 a is illustrated for reference.It is seen that the multi-directional scanning light scans a wider rangethan the scanning light 10 b emitted through the second read window 13b.

Now, a description will be made of the reason why the scanning light 10b emitted through the second read window 13 b of the reader shown inFIGS. 76A and 76B is not irradiated vertically to a read surface.

FIG. 77A is a diagram showing a state in which scanning light isirradiated vertically to a bar code. Scanning light falls on the barcode vertically. The scanning light is therefore reflected from thebar-code surface substantially in its entirety. The quantity of lightreflected from the bar code and received by the reader is therefore verylarge. When the reader is used as a touch reader, the distance of theread window employed from a bar code is so short that the quantity ofscanning light irradiated to the bar code is great. When scanning lightis irradiated vertically to a bar code in this read form, such a problemmay occur that it becomes hard to detect the contrast of the bar codebecause of the too large quantity of reflected light and the bar codecannot therefore be read.

In the conventional touch reader in which an LED is used to illuminate abar code, the quantity of light used to illuminate a bar code is not solarge as to pose the foregoing problem. In the reader of thisembodiment, however, since laser light is used to scan a bar code, thequantity of light reflected from the bar code is much larger than thatin the touch reader using an LED.

In the reader shown in FIGS. 76A and 76B, it is designed that theemission direction of scanning light emitted through the second readwindow 13 b is not vertical to a bar-code surface. When scanning lightis emitted in such an angle, as shown in FIG. 77B, the scanning light isreflected irregularly from the bar-code surface. The quantity ofreflected light received by the reader is smaller than the quantity ofreflected light of scanning light that is irradiated vertically. Sincethe distance of a bar code from the reader is very small, this reductionin quantity of reflected light does not adversely affect bar-codereading at all.

As mentioned above, since scanning light emitted through the second readwindow 13 b and used to read a closely-located bar code is irradiated inthe direction shown in FIGS. 76A and 76B, it can be prevented that thequantity of light reflected from the bar code becomes too large.Moreover, the quantity of reflected light can be optimized for detectionof a bar code.

FIG. 78 is a side sectional view of the reader of this embodiment.

A printed-circuit board 120 including a control unit for controlling thereader is incorporated in the reader. The printed-circuit board extendsfrom the head to the rear end of the grip. An interface cable 3 to becoupled with an external unit is joined with one end of theprinted-circuit board.

A laser light source 21, a condenser 26, a polygon mirror 22, multi-beamstationary mirrors 23-1 to 23-7, a single-beam stationary mirror 23-8,and a condensing sensor 25 are incorporated in the head of the reader.The multi-beam stationary mirrors 23-1 to 23-7 correspond to the floormirrors 23-1 to 23-7 in FIG. 7, and the single-beam stationary mirror23-8 corresponds to the floor mirror 23-8 in FIG. 7. The other componentelements correspond to those shown in FIG. 7.

The stationary mirrors are locked in an optical frame 122. The opticalframe is attached to a cover 121 of the reader via cushioning members124 and 125. Since the reader of the embodiment may be used as ahand-held reader, there is a fear that the reader may suffer a shockwhen it is used to read a bar code or mounted or dismounted on or fromthe stand. When shocks are conveyed to an optical system in the reader,there arises a fear that the optical system may be displaced or damaged.In the reader shown in FIG. 71, the optical frame 122 in which theoptical system is locked is attached to the cover of the reader via thecushioning members 124 and 125 so that shocks applied to the reader willnot be conveyed to the optical system.

A motor 221 for driving the polygon mirror 22 is especially susceptibleto shocks. When the motor receives shocks, a bearing may be damaged.Consequently, a sound may occur during the rotation of the motor. Atworst, there is a possibility that the motor may fail. The polygonmirror is therefore attached to the optical frame 122 via a motorcushion 126. Owing to the operation of the motor cushion 126, inaddition to the effect of shock reduction by the cushioning members,shocks applied to the motor can be greatly attenuated.

The condensing sensor 25, laser light source 21, and condenser mirror 26are also locked in the optical frame 122, though FIG. 78 does not showthem clearly. The optical frame is attached to the reader body via thecushioning members 124 and 125. These cushioning members are used toprevent vibrations stemming from the usage of the reader as a hand-heldreader from being conveyed to the optical system.

FIG. 79 is a view showing the optical frame 122 and parts constitutingthe optical system to be locked in the optical frame. FIGS. 80 to 83 areviews showing a state in which the optical parts are locked in theoptical frame 122.

The optical frame 122 is molded as a united body using, for example, aresin. The eight floor mirrors 23-1 to 23-8, condenser mirror 26, laserlight source 21, light reception sensor 25, polygon mirror 22 (polygonmotor), and cushioning members and motor cushions 124, 125, and 126 arelocked in the optical frame 122.

The reflection surfaces of the polygon mirror 22 are affixed torespective sides of a base whose cross section is shaped like atrapezoid. Alternatively, the polygon mirror may be molded as a unitedbody using a resin, and reflection membranes may be deposited on thereflection surfaces.

The base of the polygon mirror is engaged with an axis of rotation ofthe motor 221 placed on a substrate. Leads over which signals or thelike used to drive the motor are fed are coupled with one end of thesubstrate. The polygon motor 221 is locked in the optical frame 122 viathe motor cushion 126. The polygon motor 221 is screwed to the opticalframe 122 through a screw hole bored in the substrate 120.

The light reception sensor 25 is placed on a substrate. A control unitfor controlling the light reception sensor is mounted on the substrate120. A screw hole bored in the substrate on which the light receptionsensor 25 is placed is located at a position coincident with a screwhole bored in the optical frame 122. The substrate on which the lightreception sensor 25 is placed is screwed to the optical frame 122.

The laser diode (laser light source) 21 is secured to an attachmentmember with two screws. The attachment member having the laser diode 21is screwed to an attachment plate formed on the lateral side of theoptical frame 122, whereby the laser diode is secured to the opticalframe. The emission direction of laser light emanating from the laserdiode 21 is a direction toward a small reflection mirror 26′ attached tothe center of the condenser mirror 26.

Planes on which the floor mirrors 26-1 to 26-8 are affixed is placed onthe base of the optical frame 122. The numerals written on the basecorrespond to the reference numerals denoting the floor mirrors. Thefloor mirrors are affixed to the positions.

The condenser mirror 26 has both edges thereof supported by the opticalframe 122. Both the edges have three stems which are fitted into holesbored in a first clamp and second clamp. The condenser mirror attachedto the clamps is locked in the optical frame.

FIG. 84 is a view showing the condenser mirror in enlarged form. Thestems 263 and 264 are formed on the left-hand and right-hand sides ofthe condenser mirror 26 and located coaxially. The stems 263 and 264serve as an axis of rotation of the condenser mirror 26. The stem 265 islocated under the stem 264 on the side of the condenser mirror havingthe stem 264.

FIG. 85 is a view showing the condenser mirror 26 attached to the firstand second clamps 261 and 262, and a portion of the optical frame 122 inwhich the condenser 26 is locked. A slit (first hole) 266 extendinghorizontally is formed in a first wall of the optical frame 122. Asecond hold 267 and a third hole 268 shaped like an arc with the secondhole as a center are formed in a second wall of the optical frame.

The first stem 263 of the condenser mirror 26 is fitted into the firsthole 266. The second and third stems 264 and 265 of the condenser mirrorare fitted into the second and third holes 267 and 268 of the opticalframe.

The first hole 266 of the optical frame 122 is an elongated holeextending horizontally. The side of the condenser mirror 26 having thefirst stem 263 can therefore be moved back and forth with the condensermirror locked in the optical frame 122. Moreover, the second stem 264 ofthe condenser mirror 26 is merely fitted into the second hole 267.However, the third hole 268 of the optical frame is shaped like an arcwith the second hole 267 as a center. The other side of the condensermirror 26 having the second and third stems 264 and 265 can therefor bepivoted back and forth with the second stem 264 as a fulcrum.

Owing to the foregoing structure, the condenser mirror can be moved backand forth by moving the side of the condenser mirror 26 having the firststem 263. The sideways position of the condenser mirror can thus beadjusted. Moreover, the reflection surface of the condenser mirror 26can be tilted vertically by pivoting the other side of the condensermirror 26 having the second and third stems 264 and 265. The verticalinclination of the condenser mirror can thus be adjusted.

The condenser mirror 26 incorporated in the conventional reader is fixedto a member (metallic plate) having elasticity. The angle of thecondenser mirror is adjusted by tightening and adjustment screw insertedinto the back side of the frame. This structure cannot preserve a spacebetween the condenser mirror 26 and frame.

By contrast, in the reader of this embodiment, scanning light reflectedfrom the floor mirror 23-8 must be directed toward the second readwindow 13 b. It is therefore required to preserve a space, through whichscanning light passes, behind the condenser 26. However, according tothe conventional method of attaching the condenser mirror, a sufficientspace through which scanning light can pass cannot be preserved behindthe condenser mirror 26.

In the case of the condenser mirror 26 shown in FIG. 84, both the edgesof the condenser mirror 26 are attached to the optical frame 122. Asufficient space can therefore be preserved behind the optical frame.Furthermore, alignment of the condenser mirror 26 is achieved by movingboth the edges of the condenser mirror. A mechanism for securing thecondenser mirror can be used in common as a mechanism for aligning thecondenser mirror. Consequently, the number of parts can be reduced andthe space around the condenser mirror can be saved.

Incidentally, the first and second clamps 261 and 262 each have anelongated hole. The aligned condenser mirror can be secured by screwingthe first and second clamps to the optical frame 122 through screw holesbored in the optical frame.

FIG. 80 shows the optical frame 122 in a state in which all the partsare locked in the optical frame. The floor mirror 23-8 is hidden behindthe condenser mirror 26. Likewise, the polygon mirror is hidden underthe substrate on which the light reception sensor 25 is mounted. All theoptical parts are thus locked in the optical frame, whereby the opticalsystem can be constructed as a united body. Furthermore, the effect ofthe cushioning members of absorbing shocks that may be conveyed to theoptical system can be intensified.

FIGS. 81 to 83 are, similarly to FIG. 80, views showing the opticalframe accommodating the optical parts in three directions. In FIGS. 81to 83, the polygon mirror, light reception sensor, and the like areomitted. In particular, as apparent from the top view, a sufficientspace that is wide enough for scanning light emanating from the floormirror 23-8 and light reflected from a bar code and incident to thefloor mirror 23-8 to pass is preserved between the back margin of theoptical frame 122 and the condenser mirror 26.

One cushioning member 130 having a circular cross section is attached toeach of the right-hand and left-hand sides of the optical frame 122. Thecushioning members are each formed by joining large round members with asmall round member inserted into the centers thereof. Slits formed inthe cover of the reader body are engaged with the gaps between the largeround members. Thus, the optical frame is not directly attached to thecover. Shocks applied to the reader are therefore absorbed by thecushioning members. Cushioning members are affixed onto the border ofthe optical frame, though they are not shown in FIGS. 81 to 83. Thesecushioning members are interposed between the contact surfaces of theoptical frame and reader body, and absorb shocks.

The head of the reader further comprises a multi-beam exit (first readwindow) 13 a and a single-beam exit (second read window) 13 b. Thesingle-beam exit is angled so that the emission direction of scanninglight emitted through the second read window 13 b will not be a verticaldirection. The angle at which the single-beam stationary mirror 23-8 ismounted is also defined so that scanning light will be emitted in thedirection. As shown in FIG. 78, the tip of the cover is shaped so thatwhen the cover is hit against a bar-code surface, scanning light emittedthrough the second read window 13 b will not be irradiated vertically tothe bar code.

A printed-circuit board having a control unit for controlling theoperations of the whole reader is located behind (on the right-hand sideof) the optical system incorporated in the reader. An interface cable 3to be coupled with an external unit is attached to one end of theprinted-circuit board.

A switch 127 and switch 128 are located on the back side of the reader.The switch 128 corresponds to the aforesaid mode selection switch 15 band has a switch plate. The switch 127 corresponds to the switch 15 cshown in FIG. 15 and is used to change the other functions.

The reader shown in FIG. 78 is, as already described, mounted on thestand and used as a stationary reader. In particular, when the reader iserected on the stand, if the center of gravity of the reader is locatedin an upper part of the reader, the holder section to which the readeris fitted tends to pivot because of the weight of the reader. Theorientation of the read window employed of the window mounted on thestand becomes inconstant.

The reader of this embodiment therefore has the center of gravity set aslow as possible. In particular, preferably, the center of gravity shouldbe present in the grip.

For setting the center of gravity as low as possible in the illustratedstate, in the reader of this embodiment, the polygon mirror is placedbelow the stationary mirrors. What is the heaviest among all thecomponents of the reader is the motor 221 for driving the polygonmirror. The center of gravity can be lowered by placing the motor as lowas possible.

However, the grip needs a certain length. The motor 221 for driving thepolygon mirror 22 cannot be stowed in any place other than the head.Even when the polygon mirror and motor are arranged in a lower area ofthe head, the center of gravity cannot be shifted satisfactorily. In thereader shown in FIG. 78, therefore, a weight 123 used to lower thecenter of gravity is stowed in the grip. Since there is a sufficientspace in the grip, the center of the gravity of the reader can belowered as much as possible by setting the weight in the space. Evenwhen the reader is mounted on the stand, the orientation of the readwindow employed can be kept constant.

If the center of gravity were located at an upper area, when the grip isheld, the head would feel heavier than it actually is. However, sincethe center of gravity of the reader is shifted to the grip to thegreatest extent, when a user holds the grip of the reader, he/she willnot feel the head heavy but can grasp the reader in a stable manner.

FIG. 86 is a view showing an example of a reader in which the scanningpattern supplied through the second read window 13 b has been modified.In the reader shown in FIG. 86, a plurality of scanning rays (two raysin FIG. 86) of which scan directions are mutually parallel and of whichangles of emission are slightly different from each other are emittedthrough the second read window 13 b. Thus, the scanning pattern suppliedfrom the second read window 13 b is composed of a plurality of scanningrays. Even if a bar code to be brought to the face of the read window isslightly deviated from the position of the read window, the bar code canbe scanned by either of the scanning rays. Alignment of a bar code neednot be worried about very much.

For generating a plurality of scanning rays, scanning rays reflectedfrom a plurality of reflection surfaces of the polygon mirror havingdifferent inclinations must fall on the single-beam stationary mirror.Since the inclinations of the reflection surfaces of the polygon mirrorare different from one another, the angles of incidence of scanning raysincident to the single-beam stationary mirror become different from eachother. The different angles of incidence result in different emissiondirections of the scanning rays.

For example, in the case shown in FIGS. 8 and 9, a scanning ray incidentto the floor mirror 23-8 (corresponding to the single-beam stationarymirror) is reflected only from the fourth reflection surface of thepolygon mirror. The number of scanning rays emitted through the secondread window 13 b is therefore one. However, when scanning rays arereflected from the other reflection surfaces are allowed to fall on thefloor mirror 23-8, the number of scanning rays emitted through thesecond read window 13 b increases accordingly.

FIG. 87 shows a variant of the reader shown in FIG. 86, wherein ascanning ray emitted through the second read window is scanned in rasterform. FIG. 88 is a side sectional view of a reader for realizing theraster-form scanning shown in FIG. 89. A structure shown in FIG. 88 isbasically identical to that shown in FIG. 78. FIG. 89 is a flowchartdescribing control to be given in order to select raster-form scanning.

In the reader shown in FIG. 88, a mirror driving actuator 129 is locatedbelow the single-beam mirror 23-8. The operation of the mirror drivingactuator 129 is controlled by a control unit that is not shown. When themirror driving actuator 129 is driven, the single-beam mirror 23-8 ismoved back and forth. The scan timing of scanning light reflected fromthe polygon mirror 22 and the drive timing of the mirror drivingactuator 129 are adjusted so that the scanning light emitted from thesecond read window 13 b will trace a raster-form trajectory as shown inFIG. 87.

To be more specific, when the read mode is the single-scanning mode, thecontrol unit drives the window driving actuator 129 (step 971). Thedrive timing comes after the scan by one scanning ray is completed andbefore the next scan is started. The magnitude of a drive is varieddepending on a pitch of a parallel-line pattern.

The reader shown in FIG. 87 can exert the same effect as the readershown in FIG. 86. Moreover, when a so-called two-dimensional bar codemust be read using scanning light emitted through the second readwindow, it is required to scan the two-dimensional bar code horizontallyand vertically. For reading such a two-dimensional bar code, as shown inFIG. 87, scanning the scanning light emitted through the second readwindow 13 b in raster form is very effective.

As already described, preferably, the focal position of scanning lightshould be set in the vicinity of the position of a bar code to be read.For reading a bar code through the second read window 13 b, since thebar code is located very close to the read window, the focal position ofscanning light is set in the vicinity of the second read window 13 b.Incidentally, scanning light emitted through the first read window 13 ais set at a position away from the read window because of its associatedread form.

Scanning light 10 a emitted through the first read window 13 a andscanning light 10 d emitted through the second read window 13 b areproduced by the same optical system. It is therefore very hard todifferentiate one focal position from the other. The differentiation canbe achieved to some extent by differentiating the lengths of light pathsof the scanning light in the reader. Thinking of the recent demands fora more compact reader, the lengths of the light paths cannot beincreased.

Moreover, it is also required to vary the read depths (distances in aback-and-forth direction permitting bar-code reading) of scanning lightemitted through the first and second read windows.

For reading a bar code through the first read window 13 a, there is anecessity of widening a read range three-dimensionally. It is thereforerequired to increase the read depth of scanning light emitted throughthe first read window 13 a.

By contrast, for reading a bar-code menu 4 through the second readwindow 13 b, anything other than a bar code that is an object of readingmust not be read. However, when the read depth of scanning light emittedthrough the second read window 13 b is large, while the reader is movingover the menu sheet 4, any bar code (that is not the bar code to beread) recorded on the menu sheet 4 may be read. The read depth ofscanning light emitted through the second read window 13 b must besmall.

For decreasing the read depth of scanning light, the scanning light tobe emitted is spread, or on the contrary, focused. In contrast, to makethe focal position of scanning light close to a read window, thescanning light to be emitted must be focused.

In the reader shown in FIG. 90, a beam reshaping lens 130 is placed inthe vicinity of the second read window 13 b. The beam reshaping lens 130is a convex cylindrical lens, focuses scanning light in a verticaldirection in FIG. 90, but does not change the diameter of the light in ahorizontal direction (corresponding to a scan direction). Using thiskind of beam reshaping lens, the focal position of the scanning lightcan approach the second read window. Furthermore, the read depth of thescanning light can be decreased.

Now, the reason why a cylindrical lens is used as the beam reshapinglens 130 will be described.

Especially, when the diameter of light in a vertical direction issmaller than that in a scan direction, if a printed bar code has amissing portion as shown in FIG. 91A, the thickness of a bar of the readbar code may be recognized incorrectly. That is to say, in the case ofFIG. 91A, although a bar 1 originally has a thickness a, when a missingportion thereof is scanned, the reader may recognize that the bar 1 hasa thickness b. Bar-code reading is achieved incorrectly.

When the diameter of light in the vertical direction is made larger thanthat in the scan direction, a not-missing portion of a bar can bescanned as shown in FIG. 91B. The reader detects a bar code on the basisof an entire quantity of light emanating from a portion scanned byscanning light. In the case shown in FIG. 91B, although the bar 1 has amissing portion, the reader can recognize that the bar 1 has thethickness a.

As mentioned above, when the diameter of light in the vertical directionis made larger than that in the scan direction, incorrect reading causedby the missing portion of a bar shown in FIG. 91A can be prevented.

By contrast, if the diameter of light in the scan direction were madelarger, the bar 1 and a bar 2 would be scanned by scanning lightsimultaneously as shown in FIG. 91C. This poses a problem that thereader cannot distinguish the bar 1 from the bar 2. The diameter oflight in the scan direction must not be made larger.

For the above reason, a cylindrical lens is used as the beam reshapinglens.

FIG. 92 is a variant of the reader shown in FIG. 90. In the case of thereader shown in FIG. 92, a cylindrical concave mirror is used as thefloor mirror 23-8′ in place of the cylindrical convex lens 130. In thiscase, the floor mirror 23-8′ exerts the same operation as thecylindrical convex lens. That is to say, the focal position of scanninglight is close to the second read window and the read depth of thescanning light is decreased.

When the foregoing cylindrical convex lens 130 and concave mirror areused in combination, reflected light received from a bar code can bevaried depending on a distance of the bar code.

For example, when the cylindrical concave mirror 23-8′ is used, lightreflected from a bar code is converged on the cylindrical concave mirror23-8′. The focal position of light reflected from the cylindricalconcave mirror is varied depending on a distance between the cylindricalconcave mirror and bar code. For reading a bar code through the secondread window 13 b, when the bar code is located at an optimal readposition, reflected light to be converged on the cylindrical concavemirror 23-8′ (plus a condenser mirror) must be focused on the face of alight reception sensor.

Owing to the above arrangement, light reflected from a bar code locatedaway from the second read window 13 b does not focus on the lightreception surface of the light reception sensor, but goes out of focus.The light reflected from the bar code located away from the second readwindow cannot therefore be recognized by the reader. Thus, the readdepth is substantially decreased.

A method of varying a quantity of scanning light is conceivable asanother method for adjusting a read depth. When the quantity of scanninglight diminishes, a quantity of light reflected from a bar code locatedaway from a read window decreases. The reader cannot detect thereflected light. By contrast, when the quantity of scanning light isincreased, a bar code separated by a distance comparable to the increasefrom the read window can be read.

During a period during which scanning light is being emitted through thefirst read window 13 a, the quantity of scanning light is increased.Moreover, during a period during which scanning light is being emittedthrough the second read window 13 b, the quantity of scanning light isdecreased. The degree of a change in quantity of light is set accordingto a desired read depth. Owing to this system design, the read depth ofscanning light emitted through each read window can be substantiallyadjusted without the necessity of using an optical part such as a lens.

A method similar to the one illustrated in FIGS. 36 to 39 can be adoptedas a method for identifying a read window through which scanning lightis emitted.

It is important to notify a user of the reader of whether the reader isset to the single-scanning mode or multi-scanning mode. In particular,when a bar code is read, if whichever read mode is set to read the barcode is notified, it can be reported to a user that, for example, a barcode supposed to be read in single-scanning mode has been read inmulti-scanning mode.

Take for instance a reader in which the read mode can be changed to thesingle-scanning mode by pressing the mode selection switch. In thiscase, for reading a bar-code menu, the read mode must be changed to thesingle-scanning mode. A user moves the reader close to a bar code thatis an object of reading while pressing the mode selection switch.However, in the case of a reader in which when the mode selection switchis released, the read mode is changed to the multi-scanning mode, thereis a possibility that when a user releases the mode selection switchcarelessly, the read mode is changed in the other, though the user didnot intend it.

In such a case, the possibility that a bar code that is not an object ofreading may be scanned and read using a scanning pattern suppliedthrough the first read window becomes higher. Since all bar codesrecorded on a menu sheet are valid, even if a bar code that is not adesired one is read because read modes have been changed, the readerconsiders that bar-code reading has been achieved correctly and reportsthe result of bar-code reading.

At this time, if it can be reported to the user in which read mode thereader operates or in which read mode the bar code has been read, it canbe notified whether or not the reported bar-code reading meets theuser's intention. Consequently, if necessary, input bar-code data can beinvalidated or a desired bar code may be read.

FIG. 93 is a functional block diagram of a reader capable of making suchnotification. A controller 225 controls the operations of the wholereader, and is connected to a mode selection switch 224, a laser lightsource 21, and a light detecting circuit 25. Furthermore, an LED 51 andspeaker 19, used to notify a user of a bar-code reading situation, areconnected to the controller 225.

FIG. 94 is a flowchart describing indication control for the LED used tonotify a user of a read mode in which the reader shown in FIG. 93 hasbeen set for reading a bar code.

The controller 225 first recognizes a designated read mode (step 975).When the designated read mode is the single-scanning mode, indicationcontrol for the single-scanning mode is selection (step 976). Bycontrast, when the designated read mode is the multi-scanning mode, thecontroller selects indication control for the multi-scanning mode (step977). For example, when a bar code has been read normally, the LED islit through the selected indication control (step 987).

Herein, it is preferable that an indication of the single-scanning modeand an indication of the multi-scanning mode be indicationsmutually-distinguishable at sight.

FIG. 95 is a flowchart describing control of rumbling of the speaker,which is used to notify a user of a read mode in which the reader shownin FIG. 93 has been set for reading a bar code.

The controller first recognizes a designated read mode (step 980). Whenthe designated read mode is the single-scanning mode, rumbling controlfor the single-scanning mode is selected (step 981). By contrast, whenthe designated read mode is the multi-scanning mode, the controllerselects rumbling control for the multi-scanning mode (step 982). Forexample, when a bar code is read normally (step 983), the speaker isdriven to generate a rumbling sound through the selected rumblingcontrol (step 984).

Herein, it is preferable that a rumbling sound for the single-scanningmode and a rumbling sound for the multi-scanning mode be rumbling soundsmutually-distinguishable at sight.

FIG. 96 is a flowchart describing control of varying the length of arumbling sound between the single-scanning mode and multi-scanning modein order to distinguish one read mode from the other. Herein, for thesingle-scanning mode, the rumbling sound is made longer. For themulti-scanning mode, the rumbling sound is made shorter.

The controller first recognizes a designated read mode (step 986). Whenthe designated read mode is the single-scanning mode, the controllersets the rumbling sound to a longer one (step 987). By contrast, whenthe designated read mode is the multi-scanning mode, the controller setsthe rumbling sound to a shorter one (step 988).

Thereafter, every time bar-code reading is carried out, the controllerdrives the speaker according to a designated length of the rumblingsound and allows the speaker to generate a rumbling sound (step 990).

FIG. 97 is a flowchart describing control for varying the volume of arumbling sound according to a designated read mode unlike the controldescribed in FIG. 96. In the case described in FIG. 97, in particular,the rumbling sound is made larger for the single-scanning mode, and madesmaller for the multi-scanning mode.

The controller first recognizes a designated read mode (step 991). Whenthe designated read mode is the single-scanning mode, the controllersets the rumbling sound to a larger volume (step 992). By contrast, whenthe designated read mode is the multi-scanning mode, the controller setsthe rumbling sound to a smaller volume (step 993).

Thereafter, every time bar-code reading is carried out (step 994), thecontroller drives the speaker according to a designated volume of therumbling sound and allows the speaker to generate a rumbling sound (step995).

FIG. 98 is a flowchart describing control for varying the number ofrumbling sounds given by the speaker according to a designated readmode.

The controller recognizes a designated read mode (step 996). When thedesignated read mode is the single-scanning mode, the number of rumblingsounds is set to a value specified for the single-scanning mode (forexample, one) (step 997).

By contrast, when the designated read mode is the multi-scanning mode,the controller sets the number of rumbling sounds to a value specifiedfor the multi-scanning mode (for example three) (step 998).

Thereafter, every time a bar-code is read (step 999), the controllergenerates a designated number of rumbling sounds (step 1000).

FIG. 99 is a flowchart describing control for varying the pitch of arumbling sound given by the speaker according to a read mode. In thecase shown in FIG. 99, in particular, the pitch of the rumbling sound ismade higher for the single-scanning mode.

The controller first recognizes a read mode (step 1010). When thesingle-scanning mode is designated, the controller sets the rumblingsound to a higher pitch (step 1011).

By contrast, when the designated read mode is the multi-scanning mode,the controller sets the rumbling sound to a lower pitch (step 1012).

Thereafter, every time a bar code is read (step 1013), the controlleroperates the speaker according to a designated pitch of the rumblingsound (step 1014).

FIG. 100 is a flowchart describing control for notifying a user of acurrently-set read mode using an LED indicator. Herein, the LED flickersin single-scanning mode, and is lit continually in multi-scanning mode.

First, when a read mode is selected, the controller recognizes the readmode (step 1020). When the single-scanning mode is selected, control offlickering the LED is selected and the LED flickers (step 1021). Bycontrast, when the multi-scanning mode is selected, the controllerselects control of continual lighting and the LED is lit continually(step 1022).

LED control is changed from one to the other concurrently with changingof the read mode from the multi-scanning mode to the single-scanningmode or vice versa which has been described in conjunction with FIG. 41.Specifically, when the multi-scanning mode is selected, the controllerchanges LED control into continual lighting, and gives control forvalidating the multi-scanning mode; that is, reading to be performedduring a period during which scanning light is emitted through the firstread window.

By adopting the foregoing method, a read mode set at that time can bereported to a user. Incorrect bar-code reading (reading withoutselecting a read mode that should be selected) can therefore beprevented. In particular, when the method of notifying a read modeirrespective of the result of reading is adopted, it can be reported toa user that manipulating the mode selection switch is requested.

As a method for giving different indications using the LED, aside fromthe method of flickering or continually lighting the LED, there is amethod of changing indication colors of the LED.

Incidentally, for varying a rumbling sound, an interval between rumblingsounds may be varied according to a read mode.

The reader in which the first read window 13 a and second read window 13b are independent windows has been described so far. Alternatively, asshown in FIG. 101, the number of read windows may be one. Herein, a readwindow is divided into a first area 13 c through which a scanningpattern composed of numerous rays is supplied, and second area 13 dthrough which a scanning ray suitable for reading a bar-code menu isemitted. In the case shown in FIG. 101, a mark defining the second areais inscribed around the area. This mark enables a user to identify aposition from which scanning light is emitted. Needless to say, the markneed not be inscribed on the face of the read window. As long asscanning patterns suitable for respective read modes can be supplied, anobject of the present invention can be accomplished satisfactorily.

In the embodiment described so far, a scanning pattern is supplied fromeach of the first read area and second read area. Alternatively, theareas may be united into one, and multi-scanning may be carried out inprinciple. For performing single-scanning, a specific scanning rayconstituting a multi-scanning pattern is selected, and bar-code readingis validated only during a period during which the scanning ray isemitted. In the case of the scanning pattern shown in FIG. 10, since thescanning ray E1-1 is scanning horizontally, the scanning ray E1-1 aloneis used in single-scanning mode.

In this case, it becomes unnecessary to include the floor mirror 23-8and second read window 13 b in the reader. The scanning pattern 23-8shown in FIG. 10 will not be created. Moreover, the components of theoptical system are only the floor mirrors 23-1 to 23-5 as shown in FIG.102. The reader can have an area for forming a read window reduced asshown in FIG. 103. Assuming that the specific scanning ray is a scanningray reflected from the floor mirror 23-1, in single-scanning mode,bar-code reading is validated only during a period during which thefloor mirror 23-1 is being scanned (the light source is lit, the lightreception circuit is validated, or decoding is validated).

Judging whether or not light reflected from the polygon mirror isscanning the floor mirror 23-1 is achieved by utilizing the slits formedin the polygon mirror which are shown in FIG. 36 and thereafter.Moreover, the system design for validating bar-code reading only duringa period during which the floor mirror 23-1 is being scanned is the sameas the one described previously.

In the description made so far, one read mode is changed to the otheronly during a period during which the mode selection switch is helddown. When the mode selection switch is released, the one read mode isreset. However, the mode selection switch is not limited to thisstructure. Alternatively, every time the mode selection switch ispressed (it need not be pressed continually), read modes may be changed.

1. A optical scanning device comprising: a housing; a scanner, disposedin the housing, selectively producing a first light scan pattern, and asecond light scan pattern different from the first light scan pattern;and an indicator arranged on the housing which provides an indication ofwhich light scan pattern is being emitted, wherein said indicatorproduces an audible indication of which light scan pattern is beingemitted by said scanner.
 2. An optical scanning device comprising: ahousing; a scanner, disposed in the housing, selectively producing afirst light scan pattern, and a second light scan pattern different fromthe first light scan pattern; and an indicator arranged on the housingwhich provides an indication of which light scan pattern is beingemitted, wherein said indicator is arranged on a side of the housingother than a side from which the first and second light scan patternsare emitted, and wherein said indicator provides a flicker or continuouslighting to indicate which light scan pattern is being emitted.